Problem with net.jxta.ext.config.Configurator

I'm using net.jxta.ext.config.Configurator to auto-configure a jxta
peer, in order to not input peer name, pass tcp port every time.
I've added the following code before PeerGroupFactory.newNetPeerGroup():

onfigurator conf = new Configurator(name, password);
try {
 conf.save(new File(".jxta", "PlatformConfig"));
}
catch(Exception e) {
 e.printStackTrace();
 System.exit(1);    
} 

The problem is that the discovery service starts behaving in a wierd way.
My peers don't find each other advertisements, or, after have found a
pipe advertisement in the cache, a peer isn't be able to connect to the
pipe. any hint?

thank you