diff --git a/rfbplayer/RfbProto.h b/rfbplayer/RfbProto.h
index 7ad3177..c285bbb 100644
--- a/rfbplayer/RfbProto.h
+++ b/rfbplayer/RfbProto.h
@@ -36,7 +36,7 @@
     void newSession(char *filename);
     void initialiseProtocol();
 
-    void processMsg();
+    virtual void processMsg();
 
     // serverInit() is called when the ServerInit message is received.  The
     // derived class must call on to CMsgHandler::serverInit().