problems loading Xserver. Is Xserver needed to work with GPU?

Hi,

I installed OpenCL1.1 driver on a Fedora 14 machine, according to this post: http://forums.fedoraforum.org/showthread.php?t=234595
everything went fine and the driver seemed to have been installed successfully. However the last step from the post - glxinfo | grep -i opengl - produced an error.
Later I figured out, that Xserver 1.9 failed to load with the message:

[ 24.313] dlopen: /usr/lib/xorg/extra-modules/nvidia_drv.so: undefined symbol: WindowTable

  1. How can I fix it?
  2. Can I work(compile/run/debug) with OpenCL without having Xserver? (I do it anyway via ssh)…

thank you in advance