Thanks for posting!
Just to verify, what Operating System are you running and what version of FileMaker Pro/Advanced are you using? I have duplicated the issue in a test database on Mac 10.5.5 and FileMaker Pro 8.5/9 Advanced, but did not come across the behavior with Win XP sp3.
Are you using a similar configuration?
Let me know, I have forwarded a notice to our Development and Testing department but can test and update based off of your configuration (if it is different).