JXTA P2P File Sharing

Hello,
i have created File sharing Application using JXTA and CMS libraries!
this application works fine in my Local network,but the sharing files (contents) are not visible to Peers outside my network, i mean, i cannot even find my group when it is outside my network.
how can i possibly find my group outside my network when my program is used by other peer with valid ip address?

Thanks

can you give us the source code for the application