I don't know about the issue, but I will say PLEASE DON'T USE DTA unless you REALLY REALLY know what you are doing!!!! And if you do, then you won't need it. 😎
It does HORRIBLY BAD THINGS if you just accept what it tells you to do!!
Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service