intel 2.6.0: EXA choppy, UXA has artifacts

[Khashayar Naderehvandi]

Hi!

I'm trying out the newly released intel driver on a X4500 chipset.
The stack is composed of:

* kernel 2.6.28 with the patches from
http://intellinuxgraphics.org/2008Q4.html applied
* libdrm 2.4.4
* mesa 7.3rc1
* xorg-server 1.5.99.901.
* intel driver 2.6.0

With EXA compiz becomes unusably choppy and slow. I don't know how to
explain the behavior in a good way, but it's like everything is run
through a stroboscope. Sort of.
With UXA, on the other hand, everything's smooth and nice, but there
are certain artifacts. Like this:
http://dl.getdropbox.com/u/175461/uxa-artifacts.png.

Are these issues known? Any workarounds?

Regards,
Khashayar