Comment 36 for bug 384001

I too had this same error, but I found a workaround. Set the environment variable 'LIBGL_ALWAYS_INDIRECT=yes' and then try running the program.

Example: -
  administrator@artemis:~$ glxinfo
  name of display: localhost:11.0
  Error: couldn't find RGB GLX visual or fbconfig

  administrator@artemis:~$ LIBGL_ALWAYS_INDIRECT=yes glxinfo
  name of display: localhost:11.0
  display: localhost:11 screen: 0
  direct rendering: No (LIBGL_ALWAYS_INDIRECT set)
  server glx vendor string: NVIDIA Corporation
  server glx version string: 1.4
  server glx extensions:
      GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_SGIX_fbconfig,
  ...
  ...
  ...

Works both through NX and SSH tunnelling.