psoren,
yes I have asterisk set up on the SME server. (server & Gateway mode),The sme server with the asterisk4SME contrib by cyr is installed at my office. And i have an extension at home. The problem is the SIP extension is registers sucessfully. I can make an out bound call however I can't hear any voices, after some reading I found out that the External RTP ports (10000-20000) which carry voice traffic need to be opened as well. As you have suggested I have tried typing in 10000-20000 in the box, but not sure if the ports opened up as I still cant hear any voices. Another Issue would probably be that the extension sits behind a NAT device.
I will definitely try the contrib you have suggested and post my findings.
Thanks