Here is their changelog, from the patch file:
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- patch 1.15.3
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Bug Fixes
- Fixed a communication bug affecting third party leagues.
- Alt-F6 no longer stalls the game on Windows.
- Game now works correctly on versions of Mac OS X which do not support 256-color mode.
The patch is currently not available for FTP download from the Blizzard site, but you can download it by logging into Europe. Links will be added as they become available.
WARNING - iCCup launcher is currently not starting with this patch installed!
Links
Battle.net - FTP download (1.15.3)
Battle.net - FTP download (1.15.2, in case you need to reinstall)
