Safari 5.1.5 fixes 32-bit usability bug
According to the update notes, Safari 5.1.5 Safari 5.1.5 "contains a fix for an issue that could affect website usability when running Safari in 32-bit mode."
Apple released version 5.1.4 of its web browser exactly two weeks ago, which brought a litany of enhancements including faster JavaScript performance and HTML 5 video rendering fixes.
The minor 46.4MB update is available via Apple's dedicated Safari webpage or through Software Update.