Please don't hijack other threads with the same problem. If you want to get a good answer when reporting a error, try to include all the information that is useful. For example the version of the library you are using. I can only infer from the tags that you are using aSmack. A stacktrace of the exception would also be helpful.
Finally, Smack and aSmack is open source. Nothing prevents you from taking a close look on what's going on under the hood.