Text artifacts (icons, etc) don't appear with transparency when they should - instead, they appear on a black background.
Example screenshot:
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System Specs:
ATI Radeon 9700 Pro
Catalyst Driver set version 3.7 - ati2dvag.dll 6.14.0010.6378
AMD XP2000+
512 mb Corsair PC2700 DDR
MSI KT3 Ultra 2 motherboard
Windows XP Pro