Egad.
As a short-term workaround, you can put the following lines somewhere in the beginning of glGraphicsStateGuardian_src.cxx:
#define GL_MIRROR_CLAMP_EXT 0x8742
#define GL_MIRROR_CLAMP_TO_EDGE_EXT 0x8743
#define GL_MIRROR_CLAMP_TO_BORDER_EXT 0x8912David