Compiling ... You need the mmap-2.2.3 driver installed on your system.
If you don't have the mmap-2.2.3 driver installed, you could use the driver
source in the file
xc/programs/Xserver/hw/xfree86/etc/mmapSVR3.shar
or
/usr/X11R6/lib/X11/etc/mmapSVR3.shar
Build and install the driver as instructed. You'll need the file
/usr/include/sys/mmap.h for compiling the X11R6/XFree86 source tree,
with linear addressing enabled.
The new loadable X Server is not tested to work without linear addressing.