diff --git a/ompi/mca/bcol/basesmuma/bcol_basesmuma_progress.c b/ompi/mca/bcol/basesmuma/bcol_basesmuma_progress.c
index 50b260f7d3..77263f9480 100644
--- a/ompi/mca/bcol/basesmuma/bcol_basesmuma_progress.c
+++ b/ompi/mca/bcol/basesmuma/bcol_basesmuma_progress.c
@@ -1,6 +1,8 @@
 /*
  * Copyright (c) 2009-2012 Oak Ridge National Laboratory.  All rights reserved.
  * Copyright (c) 2009-2012 Mellanox Technologies.  All rights reserved.
+ * Copyright (c) 2014      Los Alamos National Security, LLC. All rights
+ *                         reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -23,7 +25,7 @@
 int bcol_basesmuma_progress(void)
 {
     /* local variables */
-   volatile int64_t *cntr;
+    volatile int32_t *cntr;
     mca_bcol_basesmuma_component_t *cs = &mca_bcol_basesmuma_component;
 
     /* check to see if release of memory blocks needs to be done */
@@ -54,12 +56,12 @@ int bcol_basesmuma_progress(void)
                        ctl_buffs_mgmt[index].bank_gen_counter);
                      */
 
-                    cntr= (volatile int64_t *) &(item_ptr->coll_buff->
+                    cntr= (volatile int32_t *) &(item_ptr->coll_buff->
                                 ctl_buffs_mgmt[index].bank_gen_counter);
                     item_ptr=(sm_nbbar_desc_t*)opal_list_remove_item((opal_list_t *)list,
                             ( opal_list_item_t *)item_ptr);
                     /* increment the generation number */
-                    OPAL_THREAD_ADD64(cntr,1);
+                    OPAL_THREAD_ADD32(cntr,1);
                 }
             }
 
diff --git a/ompi/mca/coll/ml/coll_ml.h b/ompi/mca/coll/ml/coll_ml.h
index 56fab98f00..f8939cc2a9 100644
--- a/ompi/mca/coll/ml/coll_ml.h
+++ b/ompi/mca/coll/ml/coll_ml.h
@@ -401,7 +401,7 @@ struct mca_coll_ml_descriptor_t {
     ompi_request_t super; /*base request*/
     struct ompi_datatype_t *datatype; /*ompi datatype*/
     size_t count; /*count of user datatype elements*/
-    uint64_t sequence_num; /*sequence number for collective operation*/
+    uint32_t sequence_num; /*sequence number for collective operation*/
     size_t frags_limit; /*upper limit on # of fragments*/
     size_t frags_start; /*number of fragments started*/
 
@@ -679,10 +679,10 @@ struct mca_coll_ml_module_t {
     int max_fn_calls;
 
     /* collective sequence number - unique id for barrier type operations */
-    int64_t no_data_collective_sequence_num;
+    int32_t no_data_collective_sequence_num;
 
     /* collective sequence number - unique id for each collective */
-    int64_t collective_sequence_num;
+    int32_t collective_sequence_num;
 
     /** ompi free list of full message descriptors **/
     ompi_free_list_t message_descriptors;
@@ -994,7 +994,7 @@ void mca_coll_ml_abort_ml(char *message);
                         s_offset, r_offset, frag_len, buf)                \
 do {                                                                      \
             op->variable_fn_params.sequence_num =                         \
-            OPAL_THREAD_ADD64(&((ml)->collective_sequence_num), 1);       \
+            OPAL_THREAD_ADD32(&((ml)->collective_sequence_num), 1);       \
             op->variable_fn_params.count = cnt;                           \
             op->variable_fn_params.dtype = datatype;                      \
             op->variable_fn_params.buffer_index = (b_desc)->buffer_index; \
diff --git a/ompi/mca/coll/ml/coll_ml_barrier.c b/ompi/mca/coll/ml/coll_ml_barrier.c
index 119be6d617..9f59cf8bf1 100644
--- a/ompi/mca/coll/ml/coll_ml_barrier.c
+++ b/ompi/mca/coll/ml/coll_ml_barrier.c
@@ -65,7 +65,7 @@ static int mca_coll_ml_barrier_launch(mca_coll_ml_module_t *ml_module,
     coll_op->variable_fn_params.buffer_index = src_buffer_desc->buffer_index;
 
     coll_op->variable_fn_params.sequence_num =
-        OPAL_THREAD_ADD64(&(ml_module->collective_sequence_num), 1);
+        OPAL_THREAD_ADD32(&(ml_module->collective_sequence_num), 1);
 
     /* Pointer to a coll finalize function */
     coll_op->process_fn = NULL;
diff --git a/ompi/mca/coll/ml/coll_ml_bcast.c b/ompi/mca/coll/ml/coll_ml_bcast.c
index 83940833a5..3569b7b0eb 100644
--- a/ompi/mca/coll/ml/coll_ml_bcast.c
+++ b/ompi/mca/coll/ml/coll_ml_bcast.c
@@ -773,7 +773,7 @@ int mca_coll_ml_bcast_sequential_root(void *buf, int count, struct ompi_datatype
 
     /* Fill in the function arguments */
     coll_op->variable_fn_params.sequence_num =
-        OPAL_THREAD_ADD64(&(ml_module->collective_sequence_num), 1);
+        OPAL_THREAD_ADD32(&(ml_module->collective_sequence_num), 1);
     coll_op->variable_fn_params.count = count;
     coll_op->variable_fn_params.dtype = dtype;