diff --git a/configure.ac b/configure.ac
index 9ac2e21..54cbb9b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2980,6 +2980,11 @@ else
    AC_MSG_RESULT([int or better])
 fi
 
+# Define strict alignment memory access for alignment-sensitive platform (i.e., SPARC)
+if test "$host_cpu" = "sparc" ; then
+    AC_DEFINE(HAVE_STRICT_ALIGNMENT,1,[Define if strict alignment memory access is required])
+fi
+
 # There are further alignment checks after we test for int64_t etc. below.
 
 # Get the size of the C types for encoding in the basic datatypes and for
diff --git a/src/mpid/ch3/channels/nemesis/src/ch3_progress.c b/src/mpid/ch3/channels/nemesis/src/ch3_progress.c
index 245fe61..0ad94a7 100644
--- a/src/mpid/ch3/channels/nemesis/src/ch3_progress.c
+++ b/src/mpid/ch3/channels/nemesis/src/ch3_progress.c
@@ -752,12 +752,19 @@ int MPID_nem_handle_pkt(MPIDI_VC_t *vc, char *buf, MPIDI_msg_sz_t buflen)
                 MPIDI_msg_sz_t len = buflen;
                 MPIDI_CH3_Pkt_t *pkt = (MPIDI_CH3_Pkt_t *)buf;
 
+#ifdef HAVE_STRICT_ALIGNMENT
+                MPIDI_CH3_Pkt_t aligned_pkt_hdr;
+                MPIDI_CH3_Pkt_t *pkt_ptr = pkt;
+
+                MPIDI_CH3_Pkt_get_aligned_ptr(&aligned_pkt_hdr, buf, &pkt);
+#endif
+
                 MPIU_DBG_MSG(CH3_CHANNEL, VERBOSE, "received new message");
 
                 /* invalid pkt data will result in unpredictable behavior */
                 MPIU_Assert(pkt->type >= 0 && pkt->type < MPIDI_CH3_PKT_END_ALL);
 
-                mpi_errno = pktArray[pkt->type](vc, pkt, &len, &rreq);
+                mpi_errno = pktArray[pkt->type](vc, buf, &len, &rreq);
                 if (mpi_errno) MPIR_ERR_POP(mpi_errno);
                 buflen -= len;
                 buf    += len;
diff --git a/src/mpid/ch3/include/mpidimpl.h b/src/mpid/ch3/include/mpidimpl.h
index 51d1420..a5944c6 100644
--- a/src/mpid/ch3/include/mpidimpl.h
+++ b/src/mpid/ch3/include/mpidimpl.h
@@ -1894,4 +1894,35 @@ int MPIDI_CH3I_Progress_deactivate_hook(int id);
 #define MPID_Progress_activate_hook(id_) MPIDI_CH3I_Progress_activate_hook(id_)
 #define MPID_Progress_deactivate_hook(id_) MPIDI_CH3I_Progress_deactivate_hook(id_)
 
+
+#ifdef HAVE_STRICT_ALIGNMENT
+/* The received packet may be stored at unaligned memory address (i.e., eager message
+ * in TCP netmod), direct access is not allowed on alignment-sensitive platforms
+ * (i.e., SPARC). This function checks whether the buffer address is aligned and
+ * returns a pointer to the packet header for safe access.
+ * If the address is not aligned, then copy the packet header to the aligned
+ * temporary buffer and returns the pointer to the aligned buffer; otherwise
+ * returns the pointer to the original buffer. Note that the caller is responsible
+ * for managing the aligned temporary buffer. */
+static inline void MPIDI_CH3_Pkt_get_aligned_ptr(MPIDI_CH3_Pkt_t * aligned_buf,
+                                                 MPIDI_CH3_Pkt_t * buf, MPIDI_CH3_Pkt_t ** pkt_ptr)
+{
+    int align_sz = 8;           /* default aligns everything to 8-byte boundaries */
+#ifdef HAVE_MAX_STRUCT_ALIGNMENT
+    if (align_sz > HAVE_MAX_STRUCT_ALIGNMENT) {
+        align_sz = HAVE_MAX_STRUCT_ALIGNMENT;
+    }
+#endif
+
+    /* check alignment */
+    if (((uintptr_t) buf % align_sz) != 0) {
+        memcpy(aligned_buf, buf, sizeof(MPIDI_CH3_Pkt_t));
+        (*pkt_ptr) = aligned_buf;
+    }
+    else {
+        (*pkt_ptr) = buf;
+    }
+}
+#endif
+
 #endif /* !defined(MPICH_MPIDIMPL_H_INCLUDED) */
diff --git a/src/mpid/ch3/src/ch3u_eager.c b/src/mpid/ch3/src/ch3u_eager.c
index 1a81c5a..a17fce0 100644
--- a/src/mpid/ch3/src/ch3u_eager.c
+++ b/src/mpid/ch3/src/ch3u_eager.c
@@ -291,11 +291,21 @@ int MPIDI_CH3_EagerContigShortSend( MPID_Request **sreq_p,
 int MPIDI_CH3_PktHandler_EagerShortSend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt, 
 					 MPIDI_msg_sz_t *buflen, MPID_Request **rreqp )
 {
-    MPIDI_CH3_Pkt_eagershort_send_t * eagershort_pkt = &pkt->eagershort_send;
+    MPIDI_CH3_Pkt_eagershort_send_t * eagershort_pkt = NULL;
     MPID_Request * rreq;
     int found;
     int mpi_errno = MPI_SUCCESS;
 
+#ifdef HAVE_STRICT_ALIGNMENT
+    MPIDI_CH3_Pkt_t aligned_pkt_hdr;
+    MPIDI_CH3_Pkt_t *pkt_ptr = pkt;
+
+    MPIDI_CH3_Pkt_get_aligned_ptr(&aligned_pkt_hdr, pkt, &pkt_ptr);
+    eagershort_pkt = &pkt_ptr->eagershort_send;
+#else
+    eagershort_pkt = &pkt->eagershort_send;
+#endif
+
     MPID_THREAD_CS_ENTER(POBJ, MPIR_THREAD_POBJ_MSGQ_MUTEX);
 
     /* printf( "Receiving short eager!\n" ); fflush(stdout); */
@@ -607,7 +617,7 @@ int MPIDI_CH3_EagerContigIsend( MPID_Request **sreq_p,
 int MPIDI_CH3_PktHandler_EagerSend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt, 
 				    MPIDI_msg_sz_t *buflen, MPID_Request **rreqp )
 {
-    MPIDI_CH3_Pkt_eager_send_t * eager_pkt = &pkt->eager_send;
+    MPIDI_CH3_Pkt_eager_send_t * eager_pkt = NULL;
     MPID_Request * rreq;
     int found;
     int complete;
@@ -615,6 +625,16 @@ int MPIDI_CH3_PktHandler_EagerSend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt,
     MPIDI_msg_sz_t data_len;
     int mpi_errno = MPI_SUCCESS;
 
+#ifdef HAVE_STRICT_ALIGNMENT
+    MPIDI_CH3_Pkt_t aligned_pkt_hdr;
+    MPIDI_CH3_Pkt_t *pkt_ptr = pkt;
+
+    MPIDI_CH3_Pkt_get_aligned_ptr(&aligned_pkt_hdr, pkt, &pkt_ptr);
+    eager_pkt = &pkt_ptr->eager_send;
+#else
+    eager_pkt = &pkt->eager_send;
+#endif
+
     MPID_THREAD_CS_ENTER(POBJ, MPIR_THREAD_POBJ_MSGQ_MUTEX);
 
     MPIU_DBG_MSG_FMT(CH3_OTHER,VERBOSE,(MPIU_DBG_FDEST,
@@ -697,7 +717,7 @@ int MPIDI_CH3_PktHandler_EagerSend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt,
 int MPIDI_CH3_PktHandler_ReadySend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt,
 				    MPIDI_msg_sz_t *buflen, MPID_Request **rreqp )
 {
-    MPIDI_CH3_Pkt_ready_send_t * ready_pkt = &pkt->ready_send;
+    MPIDI_CH3_Pkt_ready_send_t * ready_pkt = NULL;
     MPID_Request * rreq;
     int found;
     int complete;
@@ -705,6 +725,16 @@ int MPIDI_CH3_PktHandler_ReadySend( MPIDI_VC_t *vc, MPIDI_CH3_Pkt_t *pkt,
     MPIDI_msg_sz_t data_len;
     int mpi_errno = MPI_SUCCESS;
     
+#ifdef HAVE_STRICT_ALIGNMENT
+    MPIDI_CH3_Pkt_t aligned_pkt_hdr;
+    MPIDI_CH3_Pkt_t *pkt_ptr = pkt;
+
+    MPIDI_CH3_Pkt_get_aligned_ptr(&aligned_pkt_hdr, pkt, &pkt_ptr);
+    ready_pkt = &pkt_ptr->ready_send;
+#else
+    ready_pkt = &pkt->ready_send;
+#endif
+
     MPIU_DBG_MSG_FMT(CH3_OTHER,VERBOSE,(MPIU_DBG_FDEST,
 	"received ready send pkt, sreq=0x%08x, rank=%d, tag=%d, context=%d",
 			ready_pkt->sender_req_id,