Xorg is very slow.

[Magicloud Magiclouds <magicloud.magiclouds@gmail.com>]

Hi,
  I am using Debian Sid, with 2.6.18 kernel. A few days ago (two
weeks? maybe), when I apt-get upgrade, I noticed that some parts of
xorg were upgraded. Then the nightmare began.
  When I started firefox, the CPU usage was full, things were very
slow. I had to kill firefox, to make everything back to normal. The
firefox is all right, nothing wrong, I belive.
  Also is openoffice, picasa, etc...
  It seemed that, xorg now is using CPU to draw the screen. So,
anything with a complex
 UI will take all CPU usage.
  Any configuration that I should modify?
  Thanks.
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