The accompanying patch allows gtk to be built on an AIX 4.2 (and presumably
other AIX versions that use X11R5) machine.  AIX divides the XShm functions
between libraries XextSam and Xext, so both are needed.

This is the first time I have worked with autoconf; if there is a more idiomatic
way to achieve the same result then feel free to change it.  I have only 
included the configure.in file on the assumption that you will want to run 
autoconf on it yourself.

Gtk and Gimp are great!  Thanks for all the work.

Beirne Konarski
beirne@neo.lrun.com
