diff --git a/src/net/java/sip/communicator/impl/gui/main/chat/toolBars/MainToolBar.java b/src/net/java/sip/communicator/impl/gui/main/chat/toolBars/MainToolBar.java
index 724026918..44b653bb4 100644
--- a/src/net/java/sip/communicator/impl/gui/main/chat/toolBars/MainToolBar.java
+++ b/src/net/java/sip/communicator/impl/gui/main/chat/toolBars/MainToolBar.java
@@ -344,7 +344,9 @@ public void chatChanged(ChatPanel chatPanel)
             sendFileButton.setEnabled(
                 chatPanel.findFileTransferChatTransport() != null);
 
-            new UpdateCallButtonWorker(contact).start();
+            // null when using chat rooms
+            if(contact != null)
+                new UpdateCallButtonWorker(contact).start();
 
             changeHistoryButtonsState(chatPanel);
         }