Changes the visibility modifier of the method that generates thread IDs for XMPP

src/net/java/sip/communicator/impl/protocol/jabber/OperationSetBasicInstantMessagingJabberImpl.java

@@ -1298,7 +1298,7 @@ public void addMessageFilters(PacketFilter filter)
      *
      * @return the next thread id.
      */
-    private static synchronized String nextThreadID() {
+    public static synchronized String nextThreadID() {
         return prefix + Long.toString(id++);
     }