Togl won't build

[Brian]

I'm trying to get Tk/Python&Mesa working, but I can't get Togl to build. I get :

gcc -shared  _glumodule.o  -lGLU -lGL -lXext -lX11 -o _glumodule.so
/usr/i586-pc-linux-gnu/bin/ld: cannot find -lXext
collect2: ld returned 1 exit status
make: *** [_glumodule.so] Error 1

I'm not a C programmer or anything, but my system *knows* how to compile stuff, what gives?

.checked ld.so.conf and /usr/X11R6/lib, where the symlink libXext.so and the libXext.so.6.3 file live, and everything looks fine. What else is there?

.tried just: 'gcc -lGL' and 'gcc -lGLU' and get regular old errors, but if I
	type:'gcc -lXext' or 'gcc -lX11'  I get:
							/usr/i586-pc-linux-gnu/bin/ld: cannot find -lXext (or X11)