http://bugs.winehq.org/show_bug.cgi?id=20469
--- Comment #5 from knan-wine@anduin.net 2009-11-06 14:53:38 --- Created an attachment (id=24571) --> (http://bugs.winehq.org/attachment.cgi?id=24571) glOrtho hack
A bit of debugging reveals that the stateblock viewport minZ and maxZ are both zero.
This hack works around it for me.