A reproducible demo file is here:
A screenflow of the problem is here:
This bug is only in Safari 5, and not in Google Chrome.
Can you check this in nightly builds from http://nightly.webkit.org/? There have been quite a fix history changes between Safari 5 and the current Chrome stable channel build.
Correct Mihai, it's working fine (as expected) in the nightly: Version 5.0.4 (6533.20.27, r80833)
I'll be sure to check the nightlies next time before filing new bug reports :) Thanks!