[ISSUE #86] fixed GetMessageStoreTimestamp not return StoreTimestamp

[ISSUE #86] fixed GetMessageStoreTimestamp not return StoreTimestamp
diff --git a/src/extern/CMessageExt.cpp b/src/extern/CMessageExt.cpp
index e854ce4..5d612d8 100644
--- a/src/extern/CMessageExt.cpp
+++ b/src/extern/CMessageExt.cpp
@@ -99,7 +99,7 @@
     if (msg == NULL) {
         return NULL_POINTER;
     }
-    return ((MQMessageExt *) msg)->getBornTimestamp();
+    return ((MQMessageExt *) msg)->getStoreTimestamp();
 }
 
 long long GetMessageQueueOffset(CMessageExt *msg){