GTK & GLIB problems

[Magnus <e97_msj nada kth se>]

Hello !
 
I have a problem with GTK and GLIB when compiling X-chat (and some other programs as well)!
I run Slackware 8, Kernel 2.4.18 and Windowmaker. 

When compiling I get 
---------------------------------
$  ./configure --with-glib-prefix=/opt/gnome/bin/ --with-gtk-prefix=/opt/gnome/bin/

...

checking for GLIB - version >= 1.2.0... no
*** The glib-config script installed by GLIB could not be found
*** If GLIB was installed in PREFIX, make sure PREFIX/bin is in
*** your path, or set the GLIB_CONFIG environment variable to the
*** full path to glib-config.
configure: warning: Cannot find GLIB! Not building GTK frontend
checking for dlopen in -ldl... (cached) yes
checking for gtk-config... (cached) no
checking for GTK - version >= 1.2.0... no
*** The gtk-config script installed by GTK could not be found
*** If GTK was installed in PREFIX, make sure PREFIX/bin is in
*** your path, or set the GTK_CONFIG environment variable to the
*** full path to gtk-config.

Cannot find GTK! Not building GTK FrontEnd.

...

---------------------------------

Putting the paths in GLIB_CONFIG and GTK_CONFIG respectively as suggested doesn't help! Neither does anything else it seems... 

---------------------------------
$ locate gtk-config glib-config
/opt/gnome/bin/gtk-config
/opt/gnome/man/man1/gtk-config.1.gz
/opt/gnome/bin/glib-config
/opt/gnome/man/man1/glib-config.1.gz
---------------------------------
So they seem to be there at least ! 

I would be SO happy if you had some advice from your previous experience with the same problem so that I can get my GUI to work...!
Thank you VERY MUCH in advance!

Best regards,
Magnus 

PATH includes all that it should I think: 
---------------------------------
$ echo $PATH 
/usr/local/sbin:/usr/local/bin:/sbin:/usr/sbin:/bin:/usr/bin:/usr/local/bin:/usr/bin:/bin:/usr/X11R6/bin:/usr/games:.:/opt/gnome/bin:/usr/share/texmf/bin:/usr/openwin/bin
---------------------------------