I suspect a lot of people are going to be seeing this message in the coming months and I want to get out in front of it.  This error occurs when you create a new Team Project using the TFS 2005 client against a WSS 3.0 server.  The most common way you will get in this situation is by install a fresh TFS 2008 server install and choosing the default options and then using the 2005 client to create Team Projects.  I'm already starting to see people hit this using Beta 2.  The "full" error message in the project creation log looks like this:

Event Description: TF30162: Task "SharePointPortal" from Group "Portal" failed

Exception Type: Microsoft.TeamFoundation.Client.PcwException

Exception Message: The language id specified in the process template does not exist on the WSS server.

with a stack trace after it.

There is a fix available for this problem.  You can download the patch for the TFS2005 Team Explorer client here: https://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=7214&wa=wsignin1.0

The knowledge base article on it is here: http://support.microsoft.com/kb/932544

Brian