That error means you don't have the GLX extensions to your X server. Can you get glxgears to run or any other 3d games? If so, can you do a glxinfo and post the results?

When i try to run the game it comes up with error message:
"Xlib: extension "GLX" missing on display ":0.0".
Fatal Error: Couldn't open window."

Please help, i have a Geforce FX 5200 W/ 128MB DDR with newest drivers, has anyone else had this problem with this card?