diff --git a/ompi/class/Makefile.am b/ompi/class/Makefile.am
index 40e1e28b72..96cdca075d 100644
--- a/ompi/class/Makefile.am
+++ b/ompi/class/Makefile.am
@@ -25,11 +25,13 @@ headers += \
         class/ompi_free_list.h \
         class/ompi_bitmap.h \
         class/ompi_pointer_array.h \
-	class/ompi_rb_tree.h
+	class/ompi_rb_tree.h \
+        class/ompi_seq_tracker.h
 
 libmpi_la_SOURCES += \
         class/ompi_bitmap.c \
         class/ompi_free_list.c \
         class/ompi_pointer_array.c \
-	class/ompi_rb_tree.c
+	class/ompi_rb_tree.c \
+        class/ompi_seq_tracker.c
 
diff --git a/ompi/class/ompi_seq_tracker.c b/ompi/class/ompi_seq_tracker.c
new file mode 100644
index 0000000000..a0d88e6623
--- /dev/null
+++ b/ompi/class/ompi_seq_tracker.c
@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
+ *                         University Research and Technology
+ *                         Corporation.  All rights reserved.
+ * Copyright (c) 2004-2005 The University of Tennessee and The University
+ *                         of Tennessee Research Foundation.  All rights
+ *                         reserved.
+ * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
+ *                         University of Stuttgart.  All rights reserved.
+ * Copyright (c) 2004-2005 The Regents of the University of California.
+ *                         All rights reserved.
+ * $COPYRIGHT$
+ * 
+ * Additional copyrights may follow
+ * 
+ * $HEADER$
+ */
+
+#include "ompi_config.h"
+
+#include "ompi/class/ompi_seq_tracker.h"
+#include "opal/sys/cache.h"
+#include "opal/util/output.h"
+
+
+
+OBJ_CLASS_INSTANCE(ompi_seq_tracker_range_t, 
+                   opal_list_item_t, 
+                   NULL, 
+                   NULL);
+
+
+static void ompi_seq_tracker_construct(ompi_seq_tracker_t* seq_tracker) { 
+    OBJ_CONSTRUCT(&seq_tracker->seq_ids, opal_list_t);
+    seq_tracker->seq_ids_current = NULL;
+}
+
+
+static void ompi_seq_tracker_destruct(ompi_seq_tracker_t* seq_tracker) { 
+    OBJ_DESTRUCT(&seq_tracker->seq_ids);
+}
+
+OBJ_CLASS_INSTANCE(
+                   ompi_seq_tracker_t,
+                   opal_object_t,
+                   ompi_seq_tracker_construct,
+                   ompi_seq_tracker_destruct);
+
+
+/**
+ *  Look for duplicate sequence number in current range.
+ *  Must be called w/ matching lock held.
+ */
+
+bool ompi_seq_tracker_check_duplicate(
+    ompi_seq_tracker_t* seq_tracker, 
+    uint32_t seq_id) 
+{ 
+    ompi_seq_tracker_range_t* item;
+    int8_t direction = 0; /* 1 is next, -1 is previous */
+
+    item = seq_tracker->seq_ids_current;
+    while(true) { 
+        if(NULL == item) { 
+            return false;
+        } else if(item->seq_id_high >= seq_id && item->seq_id_low <= seq_id) { 
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) item;
+            return true; 
+        } else if(seq_id > item->seq_id_high && direction != -1) { 
+            direction = 1; 
+            item = (ompi_seq_tracker_range_t*) opal_list_get_next(item); 
+        } else if(seq_id < item->seq_id_low && direction != 1) { 
+            direction = -1;
+            item = (ompi_seq_tracker_range_t*) opal_list_get_prev(item); 
+        } else { 
+            return false;
+        }
+    }
+}
+
+
+/*
+ * insert item into sequence tracking list,
+ *   compacts continuous regions into a single entry
+ */
+void ompi_seq_tracker_insert(ompi_seq_tracker_t* seq_tracker, 
+                                                uint32_t seq_id) 
+{ 
+    opal_list_t* seq_ids = &seq_tracker->seq_ids; 
+    ompi_seq_tracker_range_t* item = seq_tracker->seq_ids_current;
+    int8_t direction = 0; /* 1 is next, -1 is previous */
+    ompi_seq_tracker_range_t *new_item, *next_item, *prev_item;
+    while(true) { 
+        if( item == NULL || item == (ompi_seq_tracker_range_t*) &seq_ids->opal_list_tail )  { 
+            new_item = OBJ_NEW(ompi_seq_tracker_range_t);
+            new_item->seq_id_low = new_item->seq_id_high = seq_id; 
+            opal_list_append(seq_ids, (opal_list_item_t*) new_item);
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) new_item;
+            return;
+        } else if( item == (ompi_seq_tracker_range_t*) &seq_ids->opal_list_head ) { 
+            new_item = OBJ_NEW(ompi_seq_tracker_range_t);
+            new_item->seq_id_low = new_item->seq_id_high = seq_id; 
+            opal_list_prepend(seq_ids, (opal_list_item_t*) new_item); 
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) new_item;
+            return; 
+            
+        } else if(item->seq_id_high >= seq_id && item->seq_id_low <= seq_id ) { 
+
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) item;
+            return; 
+
+        } else if((item->seq_id_high + 1) == seq_id) { 
+            
+            next_item = (ompi_seq_tracker_range_t*) opal_list_get_next(item); 
+            /* try to consolidate */ 
+            if(next_item && next_item->seq_id_low == (seq_id+1)) { 
+                item->seq_id_high = next_item->seq_id_high;
+                opal_list_remove_item(seq_ids, (opal_list_item_t*) next_item);
+                OBJ_RELEASE(next_item);
+            } else { 
+                item->seq_id_high = seq_id;
+            }    
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) item;
+            return; 
+            
+        } else if((item->seq_id_low - 1) == seq_id) { 
+            
+            prev_item = (ompi_seq_tracker_range_t*) opal_list_get_prev(item);
+            /* try to consolidate */
+            if(prev_item && prev_item->seq_id_high == (seq_id-1)) {  
+                item->seq_id_low = prev_item->seq_id_low;
+                opal_list_remove_item(seq_ids, (opal_list_item_t*) prev_item);
+                OBJ_RELEASE(prev_item);
+            } else { 
+                item->seq_id_low = seq_id; 
+            }
+            seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) item;
+            return; 
+            
+        } else if(seq_id > item->seq_id_high ) { 
+            if(direction == -1) { 
+                /* we have gone back in the list, and we went one item too far */ 
+                new_item = OBJ_NEW(ompi_seq_tracker_range_t);
+                new_item->seq_id_low = new_item->seq_id_high = seq_id; 
+                /* insert new_item directly before item */
+                opal_list_insert_pos(seq_ids, 
+                                     (opal_list_item_t*) item, 
+                                     (opal_list_item_t*) new_item); 
+                seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) new_item;
+                return;
+            } else { 
+                direction = 1;
+                item = (ompi_seq_tracker_range_t*) opal_list_get_next(item);
+            }
+        } else if(seq_id < item->seq_id_low) { 
+            if(direction == 1) { 
+                /* we have gone forward in the list, and we went one item too far */ 
+                new_item = OBJ_NEW(ompi_seq_tracker_range_t); 
+                next_item = (ompi_seq_tracker_range_t*) opal_list_get_next(item);
+                if(NULL == next_item) { 
+                    opal_list_append(seq_ids, (opal_list_item_t*) new_item);
+                } else { 
+                    opal_list_insert_pos(seq_ids, 
+                                         (opal_list_item_t*) next_item, 
+                                         (opal_list_item_t*) new_item); 
+                }
+                seq_tracker->seq_ids_current = (ompi_seq_tracker_range_t*) new_item;
+                return;
+            } else { 
+                direction = -1;
+                item = (ompi_seq_tracker_range_t*) opal_list_get_prev(item); 
+            }
+        } else { 
+            return;
+        }
+    }
+}
+
+
+
+
+
diff --git a/ompi/class/ompi_seq_tracker.h b/ompi/class/ompi_seq_tracker.h
new file mode 100644
index 0000000000..3117e50a81
--- /dev/null
+++ b/ompi/class/ompi_seq_tracker.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
+ *                         University Research and Technology
+ *                         Corporation.  All rights reserved.
+ * Copyright (c) 2004-2005 The University of Tennessee and The University
+ *                         of Tennessee Research Foundation.  All rights
+ *                         reserved.
+ * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
+ *                         University of Stuttgart.  All rights reserved.
+ * Copyright (c) 2004-2005 The Regents of the University of California.
+ *                         All rights reserved.
+ * $COPYRIGHT$
+ * 
+ * Additional copyrights may follow
+ * 
+ * $HEADER$
+ */
+
+#ifndef OMPI_SEQ_TRACKER_H
+#define OMPI_SEQ_TRACKER_H
+
+#include "ompi_config.h"
+#include "opal/class/opal_list.h"
+#include "opal/threads/threads.h"
+#include "opal/threads/condition.h"
+#include "ompi/constants.h"
+#include "ompi/mca/mpool/mpool.h"
+
+#if defined(c_plusplus) || defined(__cplusplus)
+extern "C" {
+#endif
+
+struct ompi_seq_tracker_range_t{ 
+    opal_list_item_t super; 
+    uint32_t seq_id_high;
+    uint32_t seq_id_low;
+}; 
+typedef struct ompi_seq_tracker_range_t ompi_seq_tracker_range_t;
+
+OMPI_DECLSPEC OBJ_CLASS_DECLARATION(ompi_seq_tracker_range_t);
+
+struct ompi_seq_tracker_t{ 
+    opal_list_t seq_ids;         /**< list of seqs id's that have been seen */
+    ompi_seq_tracker_range_t* seq_ids_current; /**< a pointer to the last place we were in the list */
+
+}; 
+typedef struct ompi_seq_tracker_t ompi_seq_tracker_t; 
+
+OMPI_DECLSPEC OBJ_CLASS_DECLARATION(ompi_seq_tracker_t);
+
+
+/**
+ *  Look for duplicate sequence number in current range.
+ *  Must be called w/ matching lock held.
+ */
+
+bool ompi_seq_tracker_check_duplicate(
+    ompi_seq_tracker_t* seq_tracker, 
+    uint32_t seq_id);
+
+
+/*
+ * insert item into sequence tracking list,
+ *   compacts continuous regions into a single entry
+ */
+void ompi_seq_tracker_insert(ompi_seq_tracker_t* seq_tracker, 
+                                                uint32_t seq_i);
+
+#if defined(c_plusplus) || defined(__cplusplus)
+}
+#endif
+#endif 
+
diff --git a/ompi/mca/pml/dr/pml_dr_comm.c b/ompi/mca/pml/dr/pml_dr_comm.c
index 29168319af..4d6218af8e 100644
--- a/ompi/mca/pml/dr/pml_dr_comm.c
+++ b/ompi/mca/pml/dr/pml_dr_comm.c
@@ -22,27 +22,6 @@
 #include "pml_dr.h"
 #include "pml_dr_comm.h"
 
-OBJ_CLASS_INSTANCE(mca_pml_dr_range_t, 
-                   opal_list_item_t, 
-                   NULL, 
-                   NULL);
-
-
-static void mca_pml_dr_seq_tracker_construct(mca_pml_dr_seq_tracker_t* seq_tracker) { 
-    OBJ_CONSTRUCT(&seq_tracker->vfrag_ids, opal_list_t);
-    seq_tracker->vfrag_ids_current = NULL;
-}
-
-
-static void mca_pml_dr_seq_tracker_destruct(mca_pml_dr_seq_tracker_t* seq_tracker) { 
-    OBJ_DESTRUCT(&seq_tracker->vfrag_ids);
-}
-
-OBJ_CLASS_INSTANCE(
-                   mca_pml_dr_seq_tracker_t,
-                   opal_object_t,
-                   mca_pml_dr_seq_tracker_construct,
-                   mca_pml_dr_seq_tracker_destruct);
 
 static void mca_pml_dr_comm_proc_construct(mca_pml_dr_comm_proc_t* proc)
 {
@@ -53,8 +32,8 @@ static void mca_pml_dr_comm_proc_construct(mca_pml_dr_comm_proc_t* proc)
     OBJ_CONSTRUCT(&proc->specific_receives, opal_list_t);
     OBJ_CONSTRUCT(&proc->matched_receives, opal_list_t);
     OBJ_CONSTRUCT(&proc->unexpected_frags, opal_list_t);
-    OBJ_CONSTRUCT(&proc->seq_sends, mca_pml_dr_seq_tracker_t);
-    OBJ_CONSTRUCT(&proc->seq_recvs, mca_pml_dr_seq_tracker_t);
+    OBJ_CONSTRUCT(&proc->seq_sends, ompi_seq_tracker_t);
+    OBJ_CONSTRUCT(&proc->seq_recvs, ompi_seq_tracker_t);
 }
 
 
diff --git a/ompi/mca/pml/dr/pml_dr_comm.h b/ompi/mca/pml/dr/pml_dr_comm.h
index 5a311df779..5740bfb643 100644
--- a/ompi/mca/pml/dr/pml_dr_comm.h
+++ b/ompi/mca/pml/dr/pml_dr_comm.h
@@ -24,6 +24,7 @@
 #include "opal/threads/mutex.h"
 #include "opal/threads/condition.h"
 #include "opal/class/opal_list.h"
+#include "ompi/class/ompi_seq_tracker.h"
 #include "ompi/communicator/communicator.h"
 #include "ompi/proc/proc.h"
 #if defined(c_plusplus) || defined(__cplusplus)
@@ -31,24 +32,6 @@ extern "C" {
 #endif
 
 
-struct mca_pml_dr_range_t{ 
-    opal_list_item_t super; 
-    uint32_t vfrag_id_high;
-    uint32_t vfrag_id_low;
-}; 
-typedef struct mca_pml_dr_range_t mca_pml_dr_range_t;
-
-OMPI_DECLSPEC OBJ_CLASS_DECLARATION(mca_pml_dr_range_t);
-
-struct mca_pml_dr_seq_tracker_t{ 
-    opal_list_t vfrag_ids;         /**< list of vfrags id's that have been seen */
-    mca_pml_dr_range_t* vfrag_ids_current; /**< a pointer to the last place we were in the list */
-
-}; 
-typedef struct mca_pml_dr_seq_tracker_t mca_pml_dr_seq_tracker_t; 
-
-OMPI_DECLSPEC OBJ_CLASS_DECLARATION(mca_pml_dr_seq_tracker_t);
-
 struct mca_pml_dr_comm_proc_t {
     opal_object_t super;
     uint16_t expected_sequence;    /**< send message sequence number - receiver side */
@@ -63,8 +46,8 @@ struct mca_pml_dr_comm_proc_t {
     opal_list_t unexpected_frags;  /**< unexpected fragment queues */
     opal_list_t matched_receives;  /**< list of in-progress matched receives */
     ompi_proc_t* ompi_proc;        /**< back pointer to ompi_proc_t */
-    mca_pml_dr_seq_tracker_t seq_sends; /**< Tracks the send vfrags that have been acked */ 
-    mca_pml_dr_seq_tracker_t seq_recvs; /**< Tracks the receive vfrags that have been acked */ 
+    ompi_seq_tracker_t seq_sends; /**< Tracks the send vfrags that have been acked */ 
+    ompi_seq_tracker_t seq_recvs; /**< Tracks the receive vfrags that have been acked */ 
 };
 typedef struct mca_pml_dr_comm_proc_t mca_pml_dr_comm_proc_t;
 
@@ -99,134 +82,6 @@ OMPI_DECLSPEC OBJ_CLASS_DECLARATION(mca_pml_dr_comm_t);
 
 OMPI_DECLSPEC extern int mca_pml_dr_comm_init(mca_pml_dr_comm_t* dr_comm, ompi_communicator_t* ompi_comm);
 
-/**
- *  Look for duplicate sequence number in current range.
- *  Must be called w/ matching lock held.
- */
-
-static inline bool mca_pml_dr_comm_proc_check_duplicate(
-    mca_pml_dr_seq_tracker_t* seq_tracker, 
-    uint32_t vfrag_id) 
-{ 
-    mca_pml_dr_range_t* item;
-    int8_t direction = 0; /* 1 is next, -1 is previous */
-
-    item = seq_tracker->vfrag_ids_current;
-    while(true) { 
-        if(NULL == item) { 
-            return false;
-        } else if(item->vfrag_id_high >= vfrag_id && item->vfrag_id_low <= vfrag_id) { 
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) item;
-            return true; 
-        } else if(vfrag_id > item->vfrag_id_high && direction != -1) { 
-            direction = 1; 
-            item = (mca_pml_dr_range_t*) opal_list_get_next(item); 
-        } else if(vfrag_id < item->vfrag_id_low && direction != 1) { 
-            direction = -1;
-            item = (mca_pml_dr_range_t*) opal_list_get_prev(item); 
-        } else { 
-            return false;
-        }
-    }
-}
-
-
-/*
- * Must be called w/ matching lock held
- */
-static inline void mca_pml_dr_comm_proc_set_vid(mca_pml_dr_seq_tracker_t* seq_tracker, 
-                                                uint32_t vfrag_id) 
-{ 
-    opal_list_t* vfrag_ids = &seq_tracker->vfrag_ids; 
-    mca_pml_dr_range_t* item = seq_tracker->vfrag_ids_current;
-    int8_t direction = 0; /* 1 is next, -1 is previous */
-    mca_pml_dr_range_t *new_item, *next_item, *prev_item;
-    while(true) { 
-        if( item == NULL || item == (mca_pml_dr_range_t*) &vfrag_ids->opal_list_tail )  { 
-            new_item = OBJ_NEW(mca_pml_dr_range_t);
-            new_item->vfrag_id_low = new_item->vfrag_id_high = vfrag_id; 
-            opal_list_append(vfrag_ids, (opal_list_item_t*) new_item);
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) new_item;
-            return;
-        } else if( item == (mca_pml_dr_range_t*) &vfrag_ids->opal_list_head ) { 
-            new_item = OBJ_NEW(mca_pml_dr_range_t);
-            new_item->vfrag_id_low = new_item->vfrag_id_high = vfrag_id; 
-            opal_list_prepend(vfrag_ids, (opal_list_item_t*) new_item); 
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) new_item;
-            return; 
-            
-        } else if(item->vfrag_id_high >= vfrag_id && item->vfrag_id_low <= vfrag_id ) { 
-
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) item;
-            return; 
-
-        } else if((item->vfrag_id_high + 1) == vfrag_id) { 
-            
-            next_item = (mca_pml_dr_range_t*) opal_list_get_next(item); 
-            /* try to consolidate */ 
-            if(next_item && next_item->vfrag_id_low == (vfrag_id+1)) { 
-                item->vfrag_id_high = next_item->vfrag_id_high;
-                opal_list_remove_item(vfrag_ids, (opal_list_item_t*) next_item);
-                OBJ_RELEASE(next_item);
-            } else { 
-                item->vfrag_id_high = vfrag_id;
-            }    
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) item;
-            return; 
-            
-        } else if((item->vfrag_id_low - 1) == vfrag_id) { 
-            
-            prev_item = (mca_pml_dr_range_t*) opal_list_get_prev(item);
-            /* try to consolidate */
-            if(prev_item && prev_item->vfrag_id_high == (vfrag_id-1)) {  
-                item->vfrag_id_low = prev_item->vfrag_id_low;
-                opal_list_remove_item(vfrag_ids, (opal_list_item_t*) prev_item);
-                OBJ_RELEASE(prev_item);
-            } else { 
-                item->vfrag_id_low = vfrag_id; 
-            }
-            seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) item;
-            return; 
-            
-        } else if(vfrag_id > item->vfrag_id_high ) { 
-            if(direction == -1) { 
-                /* we have gone back in the list, and we went one item too far */ 
-                new_item = OBJ_NEW(mca_pml_dr_range_t);
-                new_item->vfrag_id_low = new_item->vfrag_id_high = vfrag_id; 
-                /* insert new_item directly before item */
-                opal_list_insert_pos(vfrag_ids, 
-                                     (opal_list_item_t*) item, 
-                                     (opal_list_item_t*) new_item); 
-                seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) new_item;
-                return;
-            } else { 
-                direction = 1;
-                item = (mca_pml_dr_range_t*) opal_list_get_next(item);
-            }
-        } else if(vfrag_id < item->vfrag_id_low) { 
-            if(direction == 1) { 
-                /* we have gone forward in the list, and we went one item too far */ 
-                new_item = OBJ_NEW(mca_pml_dr_range_t); 
-                next_item = (mca_pml_dr_range_t*) opal_list_get_next(item);
-                if(NULL == next_item) { 
-                    opal_list_append(vfrag_ids, (opal_list_item_t*) new_item);
-                } else { 
-                    opal_list_insert_pos(vfrag_ids, 
-                                         (opal_list_item_t*) next_item, 
-                                         (opal_list_item_t*) new_item); 
-                }
-                seq_tracker->vfrag_ids_current = (mca_pml_dr_range_t*) new_item;
-                return;
-            } else { 
-                direction = -1;
-                item = (mca_pml_dr_range_t*) opal_list_get_prev(item); 
-            }
-        } else { 
-            return;
-        }
-    }
-}
-
 
 #if defined(c_plusplus) || defined(__cplusplus)
 }
diff --git a/ompi/mca/pml/dr/pml_dr_recvfrag.c b/ompi/mca/pml/dr/pml_dr_recvfrag.c
index 09ef30ba94..70bbcc7018 100644
--- a/ompi/mca/pml/dr/pml_dr_recvfrag.c
+++ b/ompi/mca/pml/dr/pml_dr_recvfrag.c
@@ -29,6 +29,7 @@
 #include "ompi/communicator/communicator.h"
 #include "ompi/datatype/datatype.h"
 #include "ompi/mca/pml/pml.h"
+#include "ompi/class/ompi_seq_tracker.h"
 #include "pml_dr.h"
 #include "pml_dr_comm.h"
 #include "pml_dr_recvfrag.h"
@@ -121,7 +122,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_recvs protected by matching lock */
             OPAL_THREAD_LOCK(&comm->matching_lock);
-            if(mca_pml_dr_comm_proc_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
+            if(ompi_seq_tracker_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
                 OPAL_THREAD_UNLOCK(&comm->matching_lock);
                 OPAL_OUTPUT((0, "%s:%d: acking duplicate match\n", __FILE__, __LINE__));
                 mca_pml_dr_recv_frag_ack((mca_bml_base_endpoint_t*)proc->ompi_proc->proc_pml,
@@ -141,7 +142,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_sends protected by ompi_request lock*/
             OPAL_THREAD_LOCK(&ompi_request_lock);
-            if(!mca_pml_dr_comm_proc_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
+            if(!ompi_seq_tracker_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
                 OPAL_THREAD_UNLOCK(&ompi_request_lock);
                 mca_pml_dr_send_request_match_ack(btl, &hdr->hdr_ack);
             } else {
@@ -156,7 +157,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_recvs protected by matching lock */
             OPAL_THREAD_LOCK(&comm->matching_lock);
-            if(mca_pml_dr_comm_proc_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
+            if(ompi_seq_tracker_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
                 /* ack only if the vfrag has been matched */
                 mca_pml_dr_recv_request_t* recvreq = 
                     mca_pml_dr_comm_proc_check_matched(proc, hdr->hdr_common.hdr_vid);
@@ -181,7 +182,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_sends protected by ompi_request lock*/
             OPAL_THREAD_LOCK(&ompi_request_lock);
-            if(!mca_pml_dr_comm_proc_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
+            if(!ompi_seq_tracker_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
                 OPAL_THREAD_UNLOCK(&ompi_request_lock);
                 mca_pml_dr_send_request_rndv_ack(btl, &hdr->hdr_ack);
             } else {
@@ -197,7 +198,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_recvs protected by matching lock */
             OPAL_THREAD_LOCK(&comm->matching_lock);
-            if(mca_pml_dr_comm_proc_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
+            if(ompi_seq_tracker_check_duplicate(&proc->seq_recvs, hdr->hdr_common.hdr_vid)) {
                 OPAL_THREAD_UNLOCK(&comm->matching_lock);
                 OPAL_OUTPUT((0, "%s:%d: acking duplicate fragment\n", __FILE__, __LINE__));
                 mca_pml_dr_recv_frag_ack((mca_bml_base_endpoint_t*)proc->ompi_proc->proc_pml,
@@ -219,7 +220,7 @@ void mca_pml_dr_recv_frag_callback(
 
             /* seq_sends protected by ompi_request lock*/
             OPAL_THREAD_LOCK(&ompi_request_lock);
-            if(!mca_pml_dr_comm_proc_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
+            if(!ompi_seq_tracker_check_duplicate(&proc->seq_sends, hdr->hdr_common.hdr_vid)) {
                 OPAL_THREAD_UNLOCK(&ompi_request_lock);
                 mca_pml_dr_send_request_frag_ack(btl, &hdr->hdr_ack);
             } else {
@@ -659,7 +660,7 @@ rematch:
         opal_list_append(&proc->frags_cant_match, (opal_list_item_t *)frag);
     }
 
-    mca_pml_dr_comm_proc_set_vid(&proc->seq_recvs, hdr->hdr_common.hdr_vid);
+    ompi_seq_tracker_insert(&proc->seq_recvs, hdr->hdr_common.hdr_vid);
     OPAL_THREAD_UNLOCK(&comm->matching_lock);
 
     /* release matching lock before processing fragment */
diff --git a/ompi/mca/pml/dr/pml_dr_recvreq.c b/ompi/mca/pml/dr/pml_dr_recvreq.c
index 4eb818f404..0ced5ac929 100644
--- a/ompi/mca/pml/dr/pml_dr_recvreq.c
+++ b/ompi/mca/pml/dr/pml_dr_recvreq.c
@@ -287,7 +287,7 @@ void mca_pml_dr_recv_request_progress(
                 if((vfrag->vf_mask_pending & vfrag->vf_mask) == vfrag->vf_mask) { 
                     /* we have received all the pieces of the vfrag, ack 
                        everything that passed the checksum */ 
-                    mca_pml_dr_comm_proc_set_vid(&recvreq->req_proc->seq_recvs, vfrag->vf_id);
+                    ompi_seq_tracker_insert(&recvreq->req_proc->seq_recvs, vfrag->vf_id);
                     mca_pml_dr_recv_request_ack(recvreq, &hdr->hdr_common, 
                         hdr->hdr_frag.hdr_src_ptr, vfrag->vf_size, vfrag->vf_mask);
                 }
diff --git a/ompi/mca/pml/dr/pml_dr_sendreq.c b/ompi/mca/pml/dr/pml_dr_sendreq.c
index ec9aeca097..0d29775d78 100644
--- a/ompi/mca/pml/dr/pml_dr_sendreq.c
+++ b/ompi/mca/pml/dr/pml_dr_sendreq.c
@@ -24,6 +24,7 @@
 #include "ompi/constants.h"
 #include "ompi/mca/pml/pml.h"
 #include "ompi/mca/btl/btl.h"
+#include "ompi/class/ompi_seq_tracker.h"
 #include "orte/mca/errmgr/errmgr.h"
 #include "ompi/mca/mpool/mpool.h" 
 #include "pml_dr.h"
@@ -135,7 +136,7 @@ static void mca_pml_dr_match_completion(
 
         /* update statistics and complete */
         sendreq->req_bytes_delivered = sendreq->req_send.req_bytes_packed;
-        mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+        ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
         MCA_PML_DR_SEND_REQUEST_PML_COMPLETE(sendreq);
 
     /* on negative ack need to retransmit */
@@ -189,7 +190,7 @@ static void mca_pml_dr_rndv_completion(
         }
 
         /* update statistics and complete */
-        mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+        ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
         if(sendreq->req_bytes_delivered == sendreq->req_send.req_bytes_packed) {
             MCA_PML_DR_SEND_REQUEST_PML_COMPLETE(sendreq);
         } else {
@@ -257,7 +258,7 @@ static void mca_pml_dr_frag_completion(
             } 
 
             /* record vfrag id to drop duplicate acks */
-            mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+            ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
 
             /* return this vfrag */
             MCA_PML_DR_VFRAG_RETURN(vfrag);
@@ -893,7 +894,7 @@ void mca_pml_dr_send_request_match_ack(
             
             /* update statistics */
             sendreq->req_bytes_delivered = vfrag->vf_size;
-            mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+            ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
             MCA_PML_DR_SEND_REQUEST_PML_COMPLETE(sendreq);
         }
 
@@ -952,7 +953,7 @@ void mca_pml_dr_send_request_rndv_ack(
                 schedule = true;
             } 
             /* stash the vfrag id for duplicate acks.. */
-            mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+            ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
             OPAL_THREAD_UNLOCK(&ompi_request_lock);
             
             if(schedule) {
@@ -994,7 +995,6 @@ void mca_pml_dr_send_request_frag_ack(
 
     /* need to retransmit? */
     if(vfrag->vf_ack != vfrag->vf_mask) {
-        
         vfrag->vf_idx = 0;
         vfrag->vf_mask_pending = 0;
         opal_list_append(&sendreq->req_retrans, (opal_list_item_t*)vfrag);
@@ -1008,7 +1008,7 @@ void mca_pml_dr_send_request_frag_ack(
         assert(sendreq->req_bytes_delivered <= sendreq->req_send.req_bytes_packed);
 
         /* stash the vfid for duplicate acks.. */
-        mca_pml_dr_comm_proc_set_vid(&sendreq->req_proc->seq_sends, vfrag->vf_id);
+        ompi_seq_tracker_insert(&sendreq->req_proc->seq_sends, vfrag->vf_id);
         /* return vfrag */
         MCA_PML_DR_VFRAG_RETURN(vfrag);