HTC Droid Incredible 2 - Mobile Data in Germany
I found the correct answer on my own.

I needed to add an APN to get mobile internet working.

Settings -> Network Settings -> Mobile Networks -> GSM-UMTS-Options -> Access Points -> Press Menu Button -> New APN

Add the information from the following link:

http://www.androidpit.de/de/android/wiki/view/APN_Einstellungen_O2

Have phun =)!