Better Mouse Drivers For X11?

OvenMitt asks: "I've asked many people the same question and have yet to get an answer. I've RTFM over and over with no luck whatsoever. So I ask you guys: how can I get smooth mouse acceleration in XFree86 4.x? I used to remedy the situation in XFree86 3.3.x by setting the SampleRate and Resolution modifiers in the XF86Config file to some ridiculous number, but this doesn't work at all in XFree86 4.x. I'd go back to XFree86 3.3.6, but I just got a Geforce2 and my thirst for Unreal Tournament forces me to bite the bullet. I use a Kensington Expert Mouse,which is actually a very large trackball, and sometimes I feel like I'm playing marble madness when trying to get my pointer from one side of the screen to the other. Are there any alternative mouse drivers for X in development? I'd give up my Kensington Expert Mouse, but it is the absolute greatest trackball I've ever used in my life and well worth the cash IMHO."