Breakpoint 1, _mesa_enable_extension (ctx=0x51fff0, name=0x2b817e8f0fbf "GL_EXT_stencil_two_side") at main/extensions.c:459
459        set_extension(ctx, name, GL_TRUE);
(gdb) 
Continuing.
Mesa 6.5.3 implementation error: User called no-op dispatch function (an unsupported extension function?)
Please report at bugzilla.freedesktop.org

Program exited with code 01.