Hi, I'm not sure if checking for the GLX extension is such a good idea as it is possible to use OpenGL without having the GLX extension. For instance when plain Mesa is used.
Regards, Roderick -- Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! Ideal für Modem und ISDN: http://www.gmx.net/de/go/smartsurfer