tsweb, no access to TS Server

I have a sbs 2003 server and a win 2k TS application sharing server. From the Lan I can use TSweb to log on to the TS Server, but not from the internet. I can log into Remote Web workplace as admin and access the TS Server but not from client login. I have the registry setting under Hkey_Local_Machine\Software\windows\smallbusinessserver\remoteuserportol\appts=1

I suspect a dns entry between SBS 2003 and win2k server but I’m not sure how to fix it.

Also the Application server was working untill a week ago.

any other registry settings? any suggestions?