Fix for bug 84544. Check for null pointer to avoid crash. R=varada, SR=mscott, A=asa

mailnews/base/util/nsMsgProtocol.cpp

@@ -819,6 +819,8 @@ NS_IMETHODIMP nsMsgFilePostHelper::OnStartRequest(nsIRequest * aChannel, nsISupp
 
 NS_IMETHODIMP nsMsgFilePostHelper::OnStopRequest(nsIRequest * aChannel, nsISupports *ctxt, nsresult aStatus)
 {
+  if (!mProtInstance) return NS_OK; 
+
   if (!mSuspendedPostFileRead)
     mProtInstance->PostDataFinished();
 

mailnews/compose/src/nsMsgSend.cpp

@@ -224,10 +224,12 @@ NS_IMETHODIMP nsMsgComposeAndSend::GetDefaultPrompt(nsIPrompt ** aPrompt)
   /* If we cannot find a prompter, try the mail3Pane window */
   nsCOMPtr<nsIMsgWindow> msgWindow;
   nsCOMPtr <nsIMsgMailSession> mailSession (do_GetService(kMsgMailSessionCID));
+  if (mailSession)
+  {
   mailSession->GetTopmostMsgWindow(getter_AddRefs(msgWindow));
-
   if (msgWindow)
       rv = msgWindow->GetPromptDialog(aPrompt);
+  }
   
   return rv;
 }