gtk+-1.1.15 installation problems.

[Michael Schwegel <schwmic charlie cns iit edu>]

I am trying to install gtk+-1.1.15, and I get the following error when
running configure:

checking for X... no
configure: error: 
*** X libraries or include files not found. Check 'config.log' for 
*** more details.

The relevant seeming parts from config.log are:

configure:4874: checking for X
configure:4941: gcc -E  conftest.c >/dev/null 2>conftest.out
configure:4937: X11/Intrinsic.h: No such file or directory
configure: failed program was:
#line 4936 "configure"
#include "confdefs.h"
#include <X11/Intrinsic.h>


Does anyone know what exactly is not being found when configure searches
for X?  (I do indeed have X installed on my system.)  I already installed
glib and updated ld.so.conf, which looks like this:

/usr/i486-linuxaout/lib
/usr/lib
/usr/i486-linux-libc5/lib
/usr/X11R6/lib
/usr/local/lib

Any help here would be greatly appreciated.  Thanks.

-=<  Michael A. Schwegel             schwmic@charlie.cns.iit.edu >=-
-=<                                  http://www.iit.edu/~schwmic >=-