The mtxdrivers package installs a symlink /usr/lib/opengl/mtx/lib/libGL.so to ../../xorg-x11/lib/libGL.so.1.3 which is a file that does not exist as the xorg-x11 implementation uses opengl-1.2 And shouldn't it instead link to the matrox version?
*** This bug has been marked as a duplicate of bug 98144 ***