JXTA direct messenger across internet?

Question

Hi,

I downloaded the JXTA tutorials from their site. It includes a direct messenger sample program. I ran it on my home computers and it worked fine. But will it run over the internet, too? My computers are behind NAT routers, and so are most other computers out there. JXTA claims to be able to pass that, but I'm not sure if it works with the direct messenger example.

Did anyone ever try it out?

Thanks!