>> Hi Emerson,
Hi Walter!

>> Did you find a workarround for it,
Yes, in my case, in menu designer, instead of use a command, I'm using a procedure and placed Do Form command inside them.

>> or did you get any reaction from MS yet on this bug?
I've reported the bug at MS Connect site, but I have not answers.

>> I'm experiencing the same problem.
Please, validate the bug at MS Connect site:
https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=311857


Take a look at this post to know more details about this bug:
http://weblogs.foxite.com/emersonreed/archive/2007/11/23/C5_error_in_a_grid_with_user_defined_column_and_header_members.aspx