I've been experiencing pretty much the same problem, but with World of Warcraft. My current setup is Ubuntu Jaunty (9.04) with Wine 1.1.20 (packaged, not compiled from source). If I disable the key repetition, everything is OK, but when I enable it, the character seems be always starting to walk. I've also tried with Ubuntu Intrepid Ibex (8.10), with the same Wine version (different computer), and here the problem does not happen. So I guess it's Ubuntu's fault, this time... I hope this helps...