Dreamcast Internet Connection in Germany

Well, as the description says I have a US Dreamcast, I live in Germany and I want to connect the dreamcast to the internet to play games and such. Now for the question, how do I go about doing that? If anyone one can help me i would be a million times thankful. Okay now first before any other questions are asked I need to explain the situation. I use T-Online to connect to the internet and that works, but I typed the User Name, Password, and Phone Number into the dreamcast and connected that to my phone line and it said that there was no dial tone I tried changing several things, but nothing happened. So, what am I doing wrong? What should I do? Can I do anything? Also I plugged my phone cable into a hub thing that splits the line, could that be at fault? It is an american phone cable by the way not the funny looking german kind with the large connecter, but the hub is connected to wall with a german connecter and the phone and computer have no prob. That all I can say, thank you if you read this and even more thanks if you can help.
Well, I do not know what that has to do with this problem but I believe it is 3.6 or something like that. Anywho, if you think you can help in anyway, please do.