So normaly Bt server can be created like this :

server = (StreamConnectionNotifier) Connector.open(serverURL);

after that everything is fine (we use blocking accept and open method to retrieve incoming data ) :

conn = server.acceptAndOpen();

until we reach the point to terminate the server and notify that out app is closed. In books it is done like :

server.close();

And here it crashes on Nokia 6600 . On the emulator everything is fine. But on the phone it hangs. And so there was left the solution - do not close this server, just leave it ( but escape the threat which holds server.acceptAndOpen() method.