glXGetProcAddress problem

I installed a new NVIDIA card (FX5950) and its latest drivers. I tried to use the opengl extensions with glXGetProcAddress but I got a relocation error. I read some posts on this forum where someone said to use glXGetProcAddressARB instead if glXGetProcAddress doesn’t work. I tried the ARB version but I get an error saying the function was undefined. I tried including glext.h and glxext.h and every possible include. Both functions do not work so I can’t use extensions. How do I fix this problem? Is there a problem with the NVIDIA header files and/or library files? Thanks.