http://bugs.winehq.org/show_bug.cgi?id=24301
--- Comment #6 from Damjan Jovanovic damjan.jov@gmail.com 2010-09-12 02:07:50 CDT --- IIRC the rows for the AND mask are always included in the height, even if the AND mask is absent.
The absence of the AND mask is detected by the dwBytesInRes being too short to hold the AND mask data.
This may need some more testing.