Reposed here from StackOverflow because there is now a SharePoint site for just this sort of question :-)
At the bottom of every project portal dashboard page for my newly created TFS 2010 project portal (MSF Agile v5.0 template) I get the message "login failed for [DOMAIN]\sharepoint.admin" (see picture)

I am almost certain this is specifcally a SharePoint permission problem rather tehn anything TFS permission wise, but I am sufficently green with SharePoint to have little or no idea how to get to the bottom of it.
If I edit any of the dashboard pages (site actions of edit page) this message is still there, but not inside a web part which leads me to belive this is not a web part that is showing this message. But what is it? More to the point what do I need to do to fix it?
I presume I have some permissions or configuration issues, but currently both I and my companies internal support people are without a clue as to how we go about diagnosing never mind resolving this issue.
It should be pointed out that i/we are TFS 2010 newbies AND sharepoint 2007 newbies. Any help would be much apreciated.
Answered

Setting sharepoint.admin as a TFS contributor seems to have done the trick; once enough time was elapsed to have the warehose refresh. Thanks for the solution Roel.