http://www.microsoft.com/downloads/details.aspx?FamilyId=5BB36F3E-5B3D-419A-9610-2FE53815AE3B&displaylang=en

This latest service pack solves a number of issues
encountered when working with multiple CE.NET 4.x versions 4.0, 4.1 etc. the full
details are available on Amit’s weblog.