disable XShm support if one of headers sys/ipc.h, sys/shm.h or X11/extensions/XShm.h is missing.
disable XShm support if one of headers sys/ipc.h, sys/shm.h or
X11/extensions/XShm.h is missing.

kaffe/kaffe,kaffe/kaffe,kaffe/kaffe,kaffe/kaffe,kaffe/kaffe