diff -ru libSM-1.1.0.orig/src/sm_client.c libSM-1.1.0/src/sm_client.c
--- libSM-1.1.0.orig/src/sm_client.c	2008-05-12 22:30:18.000000000 +0100
+++ libSM-1.1.0/src/sm_client.c	2008-09-18 16:54:13.000000000 +0100
@@ -390,6 +390,7 @@
     pMsg->length += WORD64COUNT (bytes);
 
     pBuf = pStart = IceAllocScratch (iceConn, bytes);
+    memset(pStart, 0, bytes);
 
     STORE_LISTOF_PROPERTY (pBuf, numProps, props);