http://bugs.winehq.org/show_bug.cgi?id=15341
--- Comment #2 from V.platanias azathothgr@gmail.com 2008-09-21 08:18:39 --- Forgot to mention that debugging reports a _negative_ context extent lcOutExtY but of the same abs value as the tablet extent, which is the max_value for that axis, while the values are the same for the X axis. Perhaps the problem's there, or it's getting inverted twice.
I'm attaching a trace+wintab32 which shows this.