diff --git a/ompi/mca/btl/btl.h b/ompi/mca/btl/btl.h
index 2278db8794..90d8e957e1 100644
--- a/ompi/mca/btl/btl.h
+++ b/ompi/mca/btl/btl.h
@@ -219,6 +219,9 @@ struct mca_btl_base_header_t{
 }; 
 typedef struct mca_btl_base_header_t mca_btl_base_header_t; 
 
+#define MCA_BTL_BASE_HEADER_HTON(hdr)
+#define MCA_BTL_BASE_HEADER_NTOH(hdr)
+
 /*
  *  BTL component interface functions and datatype.
  */
diff --git a/ompi/mca/btl/tcp/btl_tcp.c b/ompi/mca/btl/tcp/btl_tcp.c
index f6609061ca..6a500af1d6 100644
--- a/ompi/mca/btl/tcp/btl_tcp.c
+++ b/ompi/mca/btl/tcp/btl_tcp.c
@@ -390,6 +390,7 @@ int mca_btl_tcp_send(
     frag->hdr.base.tag = tag;
     frag->hdr.type = MCA_BTL_TCP_HDR_TYPE_SEND;
     frag->hdr.count = 0;
+    if (endpoint->endpoint_nbo) MCA_BTL_TCP_HDR_HTON(frag->hdr);
     return mca_btl_tcp_endpoint_send(endpoint,frag);
 }
 
@@ -431,6 +432,7 @@ int mca_btl_tcp_put(
     frag->hdr.base.tag = MCA_BTL_TAG_BTL;
     frag->hdr.type = MCA_BTL_TCP_HDR_TYPE_PUT;
     frag->hdr.count = frag->base.des_dst_cnt;
+    if (endpoint->endpoint_nbo) MCA_BTL_TCP_HDR_HTON(frag->hdr);
     return mca_btl_tcp_endpoint_send(endpoint,frag);
 }
 
@@ -466,6 +468,7 @@ int mca_btl_tcp_get(
     frag->hdr.base.tag = MCA_BTL_TAG_BTL;
     frag->hdr.type = MCA_BTL_TCP_HDR_TYPE_GET;
     frag->hdr.count = frag->base.des_src_cnt;
+    if (endpoint->endpoint_nbo) MCA_BTL_TCP_HDR_HTON(frag->hdr);
     return mca_btl_tcp_endpoint_send(endpoint,frag);
 }
 
diff --git a/ompi/mca/btl/tcp/btl_tcp_component.c b/ompi/mca/btl/tcp/btl_tcp_component.c
index f1499f61fa..afa322bcd4 100644
--- a/ompi/mca/btl/tcp/btl_tcp_component.c
+++ b/ompi/mca/btl/tcp/btl_tcp_component.c
@@ -601,6 +601,7 @@ static void mca_btl_tcp_component_recv_handler(int sd, short flags, void* user)
         close(sd);
         return;
     }
+    OMPI_PROCESS_NAME_NTOH(guid);
 
     /* now set socket up to be non-blocking */
     if((flags = fcntl(sd, F_GETFL, 0)) < 0) {
diff --git a/ompi/mca/btl/tcp/btl_tcp_endpoint.c b/ompi/mca/btl/tcp/btl_tcp_endpoint.c
index 3775f37ce6..50820050b0 100644
--- a/ompi/mca/btl/tcp/btl_tcp_endpoint.c
+++ b/ompi/mca/btl/tcp/btl_tcp_endpoint.c
@@ -277,8 +277,11 @@ static int mca_btl_tcp_endpoint_send_connect_ack(mca_btl_base_endpoint_t* btl_en
 {
     /* send process identifier to remote endpoint */
     mca_btl_tcp_proc_t* btl_proc = mca_btl_tcp_proc_local();
-    if(mca_btl_tcp_endpoint_send_blocking(btl_endpoint, &btl_proc->proc_name, sizeof(btl_proc->proc_name)) != 
-          sizeof(btl_proc->proc_name)) {
+    orte_process_name_t guid = btl_proc->proc_name;
+
+    OMPI_PROCESS_NAME_HTON(guid);
+    if(mca_btl_tcp_endpoint_send_blocking(btl_endpoint, &guid, sizeof(guid)) != 
+          sizeof(guid)) {
         return OMPI_ERR_UNREACH;
     }
     return OMPI_SUCCESS;
@@ -438,6 +441,7 @@ static int mca_btl_tcp_endpoint_recv_connect_ack(mca_btl_base_endpoint_t* btl_en
     if((mca_btl_tcp_endpoint_recv_blocking(btl_endpoint, &guid, sizeof(orte_process_name_t))) != sizeof(orte_process_name_t)) {
         return OMPI_ERR_UNREACH;
     }
+    OMPI_PROCESS_NAME_NTOH(guid);
 
     /* compare this to the expected values */
     if(memcmp(&btl_proc->proc_name, &guid, sizeof(orte_process_name_t)) != 0) {
diff --git a/ompi/mca/btl/tcp/btl_tcp_frag.c b/ompi/mca/btl/tcp/btl_tcp_frag.c
index 70abf5c813..4a973b6c45 100644
--- a/ompi/mca/btl/tcp/btl_tcp_frag.c
+++ b/ompi/mca/btl/tcp/btl_tcp_frag.c
@@ -206,6 +206,7 @@ bool mca_btl_tcp_frag_recv(mca_btl_tcp_frag_t* frag, int sd)
 
     /* read header */
     if(frag->iov_cnt == 0) {
+        if (btl_endpoint->endpoint_nbo) MCA_BTL_TCP_HDR_NTOH(frag->hdr);
         switch(frag->hdr.type) {
         case MCA_BTL_TCP_HDR_TYPE_SEND:
             if(frag->iov_idx == 1 && frag->hdr.size) {
diff --git a/ompi/mca/btl/tcp/btl_tcp_hdr.h b/ompi/mca/btl/tcp/btl_tcp_hdr.h
index 89836d1de0..55b2a69e8c 100644
--- a/ompi/mca/btl/tcp/btl_tcp_hdr.h
+++ b/ompi/mca/btl/tcp/btl_tcp_hdr.h
@@ -23,6 +23,7 @@
 #include "ompi_config.h"
 #include "ompi/mca/btl/base/base.h"
 #include "btl_tcp.h" 
+#include "opal/types.h"
 
 #if defined(c_plusplus) || defined(__cplusplus)
 extern "C" {
@@ -45,6 +46,18 @@ struct mca_btl_tcp_hdr_t {
 }; 
 typedef struct mca_btl_tcp_hdr_t mca_btl_tcp_hdr_t; 
 
+#define MCA_BTL_TCP_HDR_HTON(hdr)     \
+    do {                              \
+        hdr.count = htons(hdr.count); \
+        hdr.size = hton64(hdr.size);  \
+    } while (0)
+
+#define MCA_BTL_TCP_HDR_NTOH(hdr)     \
+    do {                              \
+        hdr.count = ntohs(hdr.count); \
+        hdr.size = ntoh64(hdr.size);  \
+    } while (0)
+
 #if defined(c_plusplus) || defined(__cplusplus)
 }
 #endif
diff --git a/ompi/mca/btl/tcp/btl_tcp_proc.c b/ompi/mca/btl/tcp/btl_tcp_proc.c
index 1c17aedb25..1d445738c6 100644
--- a/ompi/mca/btl/tcp/btl_tcp_proc.c
+++ b/ompi/mca/btl/tcp/btl_tcp_proc.c
@@ -28,6 +28,7 @@
 #include "orte/class/orte_proc_table.h"
 #include "ompi/mca/btl/base/btl_base_error.h"
 #include "ompi/mca/pml/base/pml_base_module_exchange.h"
+#include "ompi/datatype/dt_arch.h"
 
 #include "btl_tcp.h"
 #include "btl_tcp_proc.h"
@@ -172,6 +173,20 @@ int mca_btl_tcp_proc_insert(
     size_t i;
     unsigned long net1;
 
+#ifndef WORDS_BIGENDIAN
+    /* if we are little endian and our peer is not so lucky, then we
+       need to put all information sent to him in big endian (aka
+       Network Byte Order) and expect all information received to
+       be in NBO.  Since big endian machines always send and receive
+       in NBO, we don't care so much about that case. */
+    if (btl_proc->proc_ompi->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        printf("setting BIGENDIAN\n");
+        btl_endpoint->endpoint_nbo = true;
+    } else {
+         printf("not setting big endian\n");
+    }
+#endif
+
     /* insert into endpoint array */
     btl_endpoint->endpoint_proc = btl_proc;
     btl_proc->proc_endpoints[btl_proc->proc_endpoint_count++] = btl_endpoint;
diff --git a/ompi/mca/osc/pt2pt/osc_pt2pt_header.h b/ompi/mca/osc/pt2pt/osc_pt2pt_header.h
index 657a7cf7cb..5363d2d584 100644
--- a/ompi/mca/osc/pt2pt/osc_pt2pt_header.h
+++ b/ompi/mca/osc/pt2pt/osc_pt2pt_header.h
@@ -21,6 +21,7 @@
 #include <netinet/in.h>
 #endif
 
+#include "opal/types.h"
 
 #define OMPI_OSC_PT2PT_HDR_PUT        0x0001
 #define OMPI_OSC_PT2PT_HDR_ACC        0x0002
@@ -134,43 +135,4 @@ typedef struct ompi_osc_pt2pt_control_header_t ompi_osc_pt2pt_control_header_t;
         (hdr).hdr_value[1] = ntohl((hdr).hdr_value[1]); \
     } while (0)
 
-
-/*
- * Convert a 64 bit value to network byte order.
- */
-static inline uint64_t hton64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = htonl(w.l[1]);
-    r.l[1] = htonl(w.l[0]);
-    return r.ll; 
-}
-
-
-/*
- * Convert a 64 bit value from network to host byte order.
- */
-static inline uint64_t ntoh64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = ntohl(w.l[1]);
-    r.l[1] = ntohl(w.l[0]);
-    return r.ll; 
-}
-
-
 #endif /* OMPI_MCA_OSC_PT2PT_HDR_H */
diff --git a/ompi/mca/pml/dr/pml_dr_hdr.h b/ompi/mca/pml/dr/pml_dr_hdr.h
index f45e9ce9b2..5438076ca7 100644
--- a/ompi/mca/pml/dr/pml_dr_hdr.h
+++ b/ompi/mca/pml/dr/pml_dr_hdr.h
@@ -29,6 +29,8 @@
 #include <netinet/in.h>
 #endif
 
+#include "opal/types.h"
+
 #define MCA_PML_DR_HDR_TYPE_MATCH     1
 #define MCA_PML_DR_HDR_TYPE_RNDV      2
 #define MCA_PML_DR_HDR_TYPE_ACK       3
@@ -39,46 +41,6 @@
 #define MCA_PML_DR_HDR_FLAGS_MATCH    4  /* is the ack in response to a match */
 
 
-/*
- * Convert a 64 bit value to network byte order.
- */
-
-static inline uint64_t hton64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = htonl(w.l[1]);
-    r.l[1] = htonl(w.l[0]);
-    return r.ll; 
-}
-
-
-/*
- * Convert a 64 bit value from network to host byte order.
- */
-
-static inline uint64_t ntoh64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = ntohl(w.l[1]);
-    r.l[1] = ntohl(w.l[0]);
-    return r.ll; 
-}
-
-
 /**
  * Common hdr attributes - must be first element in each hdr type 
  */
diff --git a/ompi/mca/pml/ob1/pml_ob1_hdr.h b/ompi/mca/pml/ob1/pml_ob1_hdr.h
index bd54288944..b2993e6238 100644
--- a/ompi/mca/pml/ob1/pml_ob1_hdr.h
+++ b/ompi/mca/pml/ob1/pml_ob1_hdr.h
@@ -29,6 +29,8 @@
 #include <netinet/in.h>
 #endif
 
+#include "opal/types.h"
+
 #define MCA_PML_OB1_HDR_TYPE_MATCH     1
 #define MCA_PML_OB1_HDR_TYPE_RNDV      2
 #define MCA_PML_OB1_HDR_TYPE_RGET      3
@@ -45,47 +47,6 @@
 #define MCA_PML_OB1_HDR_FLAGS_PIN     4  /* is user buffer pinned */
 #define MCA_PML_OB1_HDR_FLAGS_CONTIG  8  /* is user buffer contiguous */
 
-
-/*
- * Convert a 64 bit value to network byte order.
- */
-
-static inline uint64_t hton64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = htonl(w.l[1]);
-    r.l[1] = htonl(w.l[0]);
-    return r.ll; 
-}
-
-
-/*
- * Convert a 64 bit value from network to host byte order.
- */
-
-static inline uint64_t ntoh64(uint64_t val)
-{ 
-    union { uint64_t ll;                
-            uint32_t l[2]; 
-    } w, r;      
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = ntohl(w.l[1]);
-    r.l[1] = ntohl(w.l[0]);
-    return r.ll; 
-}
-
-
 /**
  * Common hdr attributes - must be first element in each hdr type 
  */
@@ -203,13 +164,13 @@ typedef struct mca_pml_ob1_ack_hdr_t mca_pml_ob1_ack_hdr_t;
 #define MCA_PML_OB1_ACK_HDR_NTOH(h) \
     do { \
     MCA_PML_OB1_COMMON_HDR_NTOH(h.hdr_common); \
-    (h).hdr_dst_size = ntoh64((h).hdr_dst_size); \
+    (h).hdr_rdma_offset = ntoh64((h).hdr_rdma_offset); \
     } while (0)
 
 #define MCA_PML_OB1_ACK_HDR_HTON(h) \
     do { \
     MCA_PML_OB1_COMMON_HDR_HTON((h).hdr_common); \
-    (h).hdr_dst_size = hton64((h).hdr_dst_size); \
+    (h).hdr_rdma_offset = hton64((h).hdr_rdma_offset); \
     } while (0) 
 
 /**
@@ -236,6 +197,16 @@ struct mca_pml_ob1_fin_hdr_t {
 };
 typedef struct mca_pml_ob1_fin_hdr_t mca_pml_ob1_fin_hdr_t;
 
+#define MCA_PML_OB1_FIN_HDR_NTOH(h) \
+    do { \
+    MCA_PML_OB1_COMMON_HDR_NTOH(h.hdr_common); \
+    } while (0)
+
+#define MCA_PML_OB1_FIN_HDR_HTON(h) \
+    do { \
+    MCA_PML_OB1_COMMON_HDR_HTON((h).hdr_common); \
+    } while (0) 
+
 /**
  * Union of defined hdr types.
  */
diff --git a/ompi/mca/pml/ob1/pml_ob1_recvfrag.c b/ompi/mca/pml/ob1/pml_ob1_recvfrag.c
index 7c0e07221c..8192237542 100644
--- a/ompi/mca/pml/ob1/pml_ob1_recvfrag.c
+++ b/ompi/mca/pml/ob1/pml_ob1_recvfrag.c
@@ -33,6 +33,7 @@
 #include "pml_ob1_recvreq.h"
 #include "pml_ob1_sendreq.h"
 #include "pml_ob1_hdr.h"
+#include "ompi/datatype/dt_arch.h"                                                                                                               
 
 
 
@@ -68,17 +69,45 @@ void mca_pml_ob1_recv_frag_callback(
         return;
     }
                                                                                                                       
+    /* hdr_type and hdr_flags are uint8_t, so no endian problems */
     switch(hdr->hdr_common.hdr_type) {
     case MCA_PML_OB1_HDR_TYPE_MATCH:
+        {
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            if (hdr->hdr_common.hdr_flags & MCA_PML_OB1_HDR_FLAGS_NBO) {
+                MCA_PML_OB1_MATCH_HDR_NTOH(hdr->hdr_match);
+            }
+#endif
+            mca_pml_ob1_recv_frag_match(btl, &hdr->hdr_match, segments,des->des_dst_cnt);
+            break;
+        }
     case MCA_PML_OB1_HDR_TYPE_RNDV:
+        {
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            if (hdr->hdr_common.hdr_flags & MCA_PML_OB1_HDR_FLAGS_NBO) {
+                MCA_PML_OB1_RNDV_HDR_NTOH(hdr->hdr_rndv);
+            }
+#endif
+            mca_pml_ob1_recv_frag_match(btl, &hdr->hdr_match, segments,des->des_dst_cnt);
+            break;
+        }
     case MCA_PML_OB1_HDR_TYPE_RGET:
         {
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            /* BWB - FIX ME - Tim, what do I do with rget? */
+#endif
             mca_pml_ob1_recv_frag_match(btl, &hdr->hdr_match, segments,des->des_dst_cnt);
             break;
         }
     case MCA_PML_OB1_HDR_TYPE_ACK:
         {
-            mca_pml_ob1_send_request_t* sendreq = (mca_pml_ob1_send_request_t*)
+            mca_pml_ob1_send_request_t* sendreq;
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            if (hdr->hdr_common.hdr_flags & MCA_PML_OB1_HDR_FLAGS_NBO) {
+                MCA_PML_OB1_ACK_HDR_NTOH(hdr->hdr_ack);
+            }
+#endif
+            sendreq = (mca_pml_ob1_send_request_t*)
                 hdr->hdr_ack.hdr_src_req.pval;
             sendreq->req_recv = hdr->hdr_ack.hdr_dst_req;
             sendreq->req_rdma_offset = hdr->hdr_ack.hdr_rdma_offset;
@@ -87,21 +116,37 @@ void mca_pml_ob1_recv_frag_callback(
         }
     case MCA_PML_OB1_HDR_TYPE_FRAG:
         {
-            mca_pml_ob1_recv_request_t* recvreq = (mca_pml_ob1_recv_request_t*)
+            mca_pml_ob1_recv_request_t* recvreq;
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            if (hdr->hdr_common.hdr_flags & MCA_PML_OB1_HDR_FLAGS_NBO) {
+                MCA_PML_OB1_FRAG_HDR_NTOH(hdr->hdr_frag);
+            }
+#endif
+            recvreq = (mca_pml_ob1_recv_request_t*)
                 hdr->hdr_frag.hdr_dst_req.pval;
             mca_pml_ob1_recv_request_progress(recvreq,btl,segments,des->des_dst_cnt);
             break;
         }
     case MCA_PML_OB1_HDR_TYPE_PUT:
         {
-            mca_pml_ob1_send_request_t* sendreq = (mca_pml_ob1_send_request_t*)
+            mca_pml_ob1_send_request_t* sendreq;
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            /* BWB - FIX ME - Tim, what do I do with rdma headers? */
+#endif
+            sendreq = (mca_pml_ob1_send_request_t*)
                 hdr->hdr_rdma.hdr_req.pval;
             mca_pml_ob1_send_request_put(sendreq,btl,&hdr->hdr_rdma);
             break;
         }
     case MCA_PML_OB1_HDR_TYPE_FIN:
         {
-            mca_btl_base_descriptor_t* rdma = (mca_btl_base_descriptor_t*)
+            mca_btl_base_descriptor_t* rdma;
+#if !defined(WORDS_BIGENDIAN) && OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+            if (hdr->hdr_common.hdr_flags & MCA_PML_OB1_HDR_FLAGS_NBO) {
+                MCA_PML_OB1_FIN_HDR_NTOH(hdr->hdr_fin);
+            }
+#endif
+            rdma = (mca_btl_base_descriptor_t*)
                 hdr->hdr_fin.hdr_des.pval;
             rdma->des_cbfunc(btl, NULL, rdma, OMPI_SUCCESS);
             break;
diff --git a/ompi/mca/pml/ob1/pml_ob1_recvreq.c b/ompi/mca/pml/ob1/pml_ob1_recvreq.c
index f4c3a09fa9..4cb1796c1b 100644
--- a/ompi/mca/pml/ob1/pml_ob1_recvreq.c
+++ b/ompi/mca/pml/ob1/pml_ob1_recvreq.c
@@ -29,7 +29,8 @@
 #include "pml_ob1_rdmafrag.h"
 #include "ompi/mca/bml/base/base.h" 
 #include "orte/mca/errmgr/errmgr.h"
-                                                                                                               
+#include "ompi/datatype/dt_arch.h"                                                                                                               
+
 static mca_pml_ob1_recv_frag_t* mca_pml_ob1_recv_request_match_specific_proc(
     mca_pml_ob1_recv_request_t* request, mca_pml_ob1_comm_proc_t* proc);
 
@@ -264,6 +265,18 @@ static void mca_pml_ob1_recv_request_ack(
     ack->hdr_dst_req.pval = recvreq;
     ack->hdr_rdma_offset = recvreq->req_rdma_offset;
 
+#ifdef WORDS_BIGENDIAN
+    ack->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (recvreq->req_recv.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        ack->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_ACK_HDR_HTON(*ack);
+    }
+#endif
+
     /* initialize descriptor */
     des->des_flags |= MCA_BTL_DES_FLAGS_PRIORITY;
     des->des_cbfunc = mca_pml_ob1_ctl_completion;
@@ -350,6 +363,18 @@ static void mca_pml_ob1_rget_completion(
     hdr->hdr_common.hdr_flags = 0;
     hdr->hdr_common.hdr_type = MCA_PML_OB1_HDR_TYPE_FIN;
     hdr->hdr_des = frag->rdma_hdr.hdr_rget.hdr_des;
+
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (recvreq->req_recv.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_FIN_HDR_HTON(*hdr);
+    }
+#endif
                                                                                                             
     /* queue request */
     rc = mca_bml_base_send(
@@ -716,6 +741,17 @@ void mca_pml_ob1_recv_request_schedule(mca_pml_ob1_recv_request_t* recvreq)
                 hdr->hdr_seg_cnt = dst->des_dst_cnt;
                 memcpy(hdr->hdr_segs, dst->des_dst, dst->des_dst_cnt * sizeof(mca_btl_base_segment_t));
 
+#ifdef WORDS_BIGENDIAN
+                hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+                /* if we are little endian and the remote side is big endian,
+                   we're responsible for making sure the data is in network byte
+                   order */
+                if (recvreq->req_recv.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+                    /* BWB - FIX ME - TIM, what do we do here? */
+                }
+#endif
+
                 /* update request state */
                 recvreq->req_rdma_offset += size;
                 OPAL_THREAD_ADD_SIZE_T(&recvreq->req_pipeline_depth,1);
diff --git a/ompi/mca/pml/ob1/pml_ob1_sendreq.c b/ompi/mca/pml/ob1/pml_ob1_sendreq.c
index 3b926e5386..c36e1b15a4 100644
--- a/ompi/mca/pml/ob1/pml_ob1_sendreq.c
+++ b/ompi/mca/pml/ob1/pml_ob1_sendreq.c
@@ -33,6 +33,7 @@
 #include "pml_ob1_recvreq.h"
 #include "pml_ob1_endpoint.h"
 #include "ompi/mca/bml/base/base.h"
+#include "ompi/datatype/dt_arch.h"
 
                                                                                                          
 static int mca_pml_ob1_send_request_fini(struct ompi_request_t** request)
@@ -336,6 +337,18 @@ int mca_pml_ob1_send_request_start_buffered(
     hdr->hdr_rndv.hdr_msg_length = sendreq->req_send.req_bytes_packed;
     hdr->hdr_rndv.hdr_src_req.pval = sendreq;
 
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_RNDV_HDR_HTON(hdr->hdr_rndv);
+    }
+#endif
+
     /* update lengths */
     segment->seg_len = sizeof(mca_pml_ob1_rendezvous_hdr_t) + max_data;
     sendreq->req_send_offset = max_data;
@@ -437,6 +450,18 @@ int mca_pml_ob1_send_request_start_copy(
     hdr->hdr_match.hdr_tag = sendreq->req_send.req_base.req_tag;
     hdr->hdr_match.hdr_seq = sendreq->req_send.req_base.req_sequence;
 
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_MATCH_HDR_HTON(hdr->hdr_match);
+    }
+#endif
+
     /* update lengths */
     segment->seg_len = sizeof(mca_pml_ob1_match_hdr_t) + max_data;
     sendreq->req_send_offset = max_data;
@@ -497,6 +522,18 @@ int mca_pml_ob1_send_request_start_prepare(
     hdr->hdr_match.hdr_tag = sendreq->req_send.req_base.req_tag;
     hdr->hdr_match.hdr_seq = sendreq->req_send.req_base.req_sequence;
 
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_MATCH_HDR_HTON(hdr->hdr_match);
+    }
+#endif
+
     /* short message */
     descriptor->des_cbfunc = mca_pml_ob1_match_completion_free;
        
@@ -578,6 +615,19 @@ int mca_pml_ob1_send_request_start_rdma(
          hdr->hdr_rndv.hdr_src_req.pval = sendreq;
          hdr->hdr_rget.hdr_des.pval = src;
          hdr->hdr_rget.hdr_seg_cnt = src->des_src_cnt;
+
+#ifdef WORDS_BIGENDIAN
+         hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+         /* if we are little endian and the remote side is big endian,
+            we're responsible for making sure the data is in network byte
+            order */
+         if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+             /* BWB - FIX ME - Ask Tim what we are supposed to do in this case */
+             return OMPI_ERR_NOT_SUPPORTED;
+         }
+#endif
+
          for(i=0; i<src->des_src_cnt; i++)
              hdr->hdr_rget.hdr_segs[i] = src->des_src[i];
          des->des_cbfunc = mca_pml_ob1_ctl_completion;
@@ -605,6 +655,18 @@ int mca_pml_ob1_send_request_start_rdma(
          hdr->hdr_rndv.hdr_msg_length = sendreq->req_send.req_bytes_packed;
          hdr->hdr_rndv.hdr_src_req.pval = sendreq;
 
+#ifdef WORDS_BIGENDIAN
+         hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+         /* if we are little endian and the remote side is big endian,
+            we're responsible for making sure the data is in network byte
+            order */
+         if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+             hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+             MCA_PML_OB1_RNDV_HDR_HTON(hdr->hdr_rndv);
+         }
+#endif
+
          /* update lengths with number of bytes actually packed */
          segment->seg_len = sizeof(mca_pml_ob1_rendezvous_hdr_t);
          sendreq->req_send_offset = 0;
@@ -674,6 +736,18 @@ int mca_pml_ob1_send_request_start_rndv(
     hdr->hdr_rndv.hdr_msg_length = sendreq->req_send.req_bytes_packed;
     hdr->hdr_rndv.hdr_src_req.pval = sendreq;
 
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_RNDV_HDR_HTON(hdr->hdr_rndv);
+    }
+#endif
+
     /* first fragment of a long message */
     des->des_flags |= MCA_BTL_DES_FLAGS_PRIORITY;
     des->des_cbdata = sendreq;
@@ -796,6 +870,18 @@ int mca_pml_ob1_send_request_schedule(mca_pml_ob1_send_request_t* sendreq)
                 hdr->hdr_src_req.pval = sendreq;
                 hdr->hdr_dst_req = sendreq->req_recv;
 
+#ifdef WORDS_BIGENDIAN
+                hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+                /* if we are little endian and the remote side is big endian,
+                   we're responsible for making sure the data is in network byte
+                   order */
+                if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+                    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+                    MCA_PML_OB1_FRAG_HDR_HTON(*hdr);
+                }
+#endif
+
                 /* update state */
                 sendreq->req_send_offset += size;
                 OPAL_THREAD_ADD_SIZE_T(&sendreq->req_pipeline_depth,1);
@@ -897,6 +983,18 @@ static void mca_pml_ob1_put_completion(
     hdr->hdr_common.hdr_type = MCA_PML_OB1_HDR_TYPE_FIN;
     hdr->hdr_des = frag->rdma_hdr.hdr_rdma.hdr_des;
 
+#ifdef WORDS_BIGENDIAN
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+    /* if we are little endian and the remote side is big endian,
+       we're responsible for making sure the data is in network byte
+       order */
+    if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) {
+        hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+        MCA_PML_OB1_FIN_HDR_HTON(*hdr);
+    }
+#endif
+
     /* queue request */
     rc = mca_bml_base_send(
                            bml_btl,
diff --git a/ompi/mca/pml/ob1/pml_ob1_sendreq.h b/ompi/mca/pml/ob1/pml_ob1_sendreq.h
index 302a2d0330..0f813a1548 100644
--- a/ompi/mca/pml/ob1/pml_ob1_sendreq.h
+++ b/ompi/mca/pml/ob1/pml_ob1_sendreq.h
@@ -29,6 +29,7 @@
 #include "pml_ob1_hdr.h"
 #include "pml_ob1_rdma.h"
 #include "ompi/datatype/convertor.h"
+#include "ompi/datatype/dt_arch.h"
 #include "ompi/mca/bml/bml.h" 
 
 #if defined(c_plusplus) || defined(__cplusplus)
@@ -108,6 +109,22 @@ OBJ_CLASS_DECLARATION(mca_pml_ob1_send_request_t);
  * Start a send request. 
  */
 
+#ifdef WORDS_BIGENDIAN
+#define MCA_PML_OB1_SEND_REQUEST_START_MATCH_FIXUP(sendreq, hdr) \
+    hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO;
+#elif OMPI_ENABLE_HETEROGENEOUS_SUPPORT
+#define MCA_PML_OB1_SEND_REQUEST_START_MATCH_FIXUP(sendreq, hdr) \
+    do { \
+        if (sendreq->req_send.req_base.req_proc->proc_arch & OMPI_ARCH_ISBIGENDIAN) { \
+            hdr->hdr_common.hdr_flags |= MCA_PML_OB1_HDR_FLAGS_NBO; \
+            MCA_PML_OB1_MATCH_HDR_HTON(hdr->hdr_match); \
+        } \
+    } while (0)
+#else
+#define MCA_PML_OB1_SEND_REQUEST_START_MATCH_FIXUP(sendreq, hdr)
+#endif
+
+
 #define MCA_PML_OB1_SEND_REQUEST_START(sendreq, rc)                                            \
 do {                                                                                           \
     mca_pml_ob1_comm_t* comm = sendreq->req_send.req_base.req_comm->c_pml_comm;                \
@@ -173,6 +190,7 @@ do {
                 hdr->hdr_match.hdr_src = sendreq->req_send.req_base.req_comm->c_my_rank;       \
                 hdr->hdr_match.hdr_tag = sendreq->req_send.req_base.req_tag;                   \
                 hdr->hdr_match.hdr_seq = sendreq->req_send.req_base.req_sequence;              \
+                MCA_PML_OB1_SEND_REQUEST_START_MATCH_FIXUP(sendreq, hdr);                      \
                                                                                                \
                 /* short message */                                                            \
                 descriptor->des_cbfunc = mca_pml_ob1_match_completion_cache;                   \
diff --git a/opal/include/opal/types.h b/opal/include/opal/types.h
index cb9304975e..9cf1a6dc39 100644
--- a/opal/include/opal/types.h
+++ b/opal/include/opal/types.h
@@ -103,4 +103,42 @@ typedef socklen_t ompi_socklen_t;
 typedef int ompi_socklen_t;
 #endif
 
+
+/*
+ * Convert a 64 bit value to network byte order.
+ */
+static inline uint64_t hton64(uint64_t val)
+{
+    union { uint64_t ll;
+            uint32_t l[2];
+    } w, r;
+
+    /* platform already in network byte order? */
+    if(htonl(1) == 1L)
+        return val;
+    w.ll = val;
+    r.l[0] = htonl(w.l[1]);
+    r.l[1] = htonl(w.l[0]);
+    return r.ll;
+}
+
+/*
+ * Convert a 64 bit value from network to host byte order.
+ */
+
+static inline uint64_t ntoh64(uint64_t val)
+{
+    union { uint64_t ll;
+            uint32_t l[2];
+    } w, r;
+
+    /* platform already in network byte order? */
+    if(htonl(1) == 1L)
+        return val;
+    w.ll = val;
+    r.l[0] = ntohl(w.l[1]);
+    r.l[1] = ntohl(w.l[0]);
+    return r.ll;
+}
+
 #endif
diff --git a/orte/mca/ns/ns_types.h b/orte/mca/ns/ns_types.h
index 4d97ea29b2..704f9435cf 100644
--- a/orte/mca/ns/ns_types.h
+++ b/orte/mca/ns/ns_types.h
@@ -89,6 +89,52 @@ typedef struct orte_process_name_t orte_process_name_t;
 extern orte_process_name_t orte_name_all;
 #define ORTE_NAME_ALL   &orte_name_all
 
+#if SIZEOF_SIZE_T == 8
+
+/**
+ * Convert process name from host to network byte order.
+ *
+ * @param name
+ */
+#define OMPI_PROCESS_NAME_HTON(n) \
+    n.cellid = hton64(n.cellid); \
+    n.jobid = hton64(n.jobid); \
+    n.vpid = hton64(n.vpid);  
+
+/**
+ * Convert process name from network to host byte order.
+ *
+ * @param name
+ */
+#define OMPI_PROCESS_NAME_NTOH(n) \
+    n.cellid = ntoh64(n.cellid); \
+    n.jobid = ntoh64(n.jobid); \
+    n.vpid = ntoh64(n.vpid); 
+
+#else
+
+/**
+ * Convert process name from host to network byte order.
+ *
+ * @param name
+ */
+#define OMPI_PROCESS_NAME_HTON(n) \
+    n.cellid = htonl(n.cellid); \
+    n.jobid = htonl(n.jobid); \
+    n.vpid = htonl(n.vpid);  
+
+/**
+ * Convert process name from network to host byte order.
+ *
+ * @param name
+ */
+#define OMPI_PROCESS_NAME_NTOH(n) \
+    n.cellid = ntohl(n.cellid); \
+    n.jobid = ntohl(n.jobid); \
+    n.vpid = ntohl(n.vpid);  
+
+#endif
+
 
 /** List of names for general use
  */
diff --git a/orte/mca/oob/tcp/oob_tcp.h b/orte/mca/oob/tcp/oob_tcp.h
index 1d27af8e76..82b0ad66f7 100644
--- a/orte/mca/oob/tcp/oob_tcp.h
+++ b/orte/mca/oob/tcp/oob_tcp.h
@@ -61,88 +61,6 @@ int mca_oob_tcp_init(void);
  */
 int mca_oob_tcp_fini(void);
 
-#if SIZEOF_SIZE_T == 8
-/*
- * Convert a 64 bit value to network byte order.
- */
-static inline uint64_t hton64(uint64_t val)
-{
-    union { uint64_t ll;
-            uint32_t l[2];
-    } w, r;
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = htonl(w.l[1]);
-    r.l[1] = htonl(w.l[0]);
-    return r.ll;
-}
-
-/*
- * Convert a 64 bit value from network to host byte order.
- */
-
-static inline uint64_t ntoh64(uint64_t val)
-{
-    union { uint64_t ll;
-            uint32_t l[2];
-    } w, r;
-
-    /* platform already in network byte order? */
-    if(htonl(1) == 1L)
-        return val;
-    w.ll = val;
-    r.l[0] = ntohl(w.l[1]);
-    r.l[1] = ntohl(w.l[0]);
-    return r.ll;
-}
-
-/**
- * Convert process name from host to network byte order.
- *
- * @param name
- */
-#define OMPI_PROCESS_NAME_HTON(n) \
-    n.cellid = hton64(n.cellid); \
-    n.jobid = hton64(n.jobid); \
-    n.vpid = hton64(n.vpid);  
-
-/**
- * Convert process name from network to host byte order.
- *
- * @param name
- */
-#define OMPI_PROCESS_NAME_NTOH(n) \
-    n.cellid = ntoh64(n.cellid); \
-    n.jobid = ntoh64(n.jobid); \
-    n.vpid = ntoh64(n.vpid); 
-
-#else
-
-/**
- * Convert process name from host to network byte order.
- *
- * @param name
- */
-#define OMPI_PROCESS_NAME_HTON(n) \
-    n.cellid = htonl(n.cellid); \
-    n.jobid = htonl(n.jobid); \
-    n.vpid = htonl(n.vpid);  
-
-/**
- * Convert process name from network to host byte order.
- *
- * @param name
- */
-#define OMPI_PROCESS_NAME_NTOH(n) \
-    n.cellid = ntohl(n.cellid); \
-    n.jobid = ntohl(n.jobid); \
-    n.vpid = ntohl(n.vpid);  
-
-#endif
-
 /**
 * Compare two process names for equality.
 *