http://bugs.winehq.org/show_bug.cgi?id=14047
--- Comment #5 from Mika Vaisanen mvaisane@mbnet.fi 2008-12-20 01:55:33 --- I can confirm this bug with Ubuntu 8.10 + Wine 1.1.10.
It is somehow related to shadows - artifacts will disappear if you disable shadows in game settings.