This bug has not been fixed on FileMaker Pro 13.
Thank you for your post, and I apologize for the late reply.
The original issue was never reported, but I have been able to replicate the issue (with both FileMaker Pro 12 and FileMaker Pro 13), and I have sent your original posting along with my findings to our Development and Testing departments for review.
Thank you for your work !
And because this thread is more than 3 months old, I almost missed it. Older threads do not pop up in to recent items when a new comment is posted. I can also reproduce this in Win 7, FMP 13.
And I can now add an entry in the Known Bugs List that is linked to this issue report.