[Wine] strange Slowdown GTA SA

[mills]

First of all Hi everybody and thanks for this cool software called "wine"

Well I've been looking for Help... I Know there is a lot about it... but I just wanted to know.... 

I have an AMD sempron 2500+ Gforce 6200 (256 MB), 1GB ram, with Ubuntu 8.10, Kde 4.1 (desktop effects disabled, no slowdowns  in opengl aplications).
Everything is ok, no sound problem.. no grafic problem.
For example Worms 4 runs perfect in wine at 60 FPS I can move a 800x600 wine window arronud and no slowdown. 

But GTA SA is... nearly unplayable (disabled pixel shader)
I tested GTA in windows and it runs perfect at 60 FPS but I don't want to use windows :(  :( . 

Why is GTA SA so slow in wine?

I forgot to say.. y tested wine 1.0.1 and also the last 1.1.19

Thanks anyway.