Thank you for your post.
I am able to replicate the problem in FileMaker Pro 11.0v2. This only occurs with Mac OS X (10.5.8 and 10.6.4), and it does not occur with versions prior to FileMaker Pro 11.
I have forwarded your post along with my findings to our Development and Software Quality Assurance (Testing) departments for review and confirmation. As more information becomes available, I will let you know.
While there were some errors, now being corrected as to the OS versions involved, this seems to be the same bug reported here:
This is one of many acknowledged bugs that can be found in the Known Bug List here in the Report an Issue section of the forum.
It can also be downloaded as a database file from: http://www.4shared.com/file/8orL8apk/FMP_Bugs.html