How to set GTK_CONFIG

[joev_nylug mindspring com]

While trying to install GIMP I get this error:

*** 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. 

So I try to set the enviroment variable:

root joev:/home/joev/stuff/gimp-1.2.1 > set GTK_CONFIG=/usr/local/bin
root joev:/home/joev/stuff/gimp-1.2.1 > set GTK_CONFIG=/usr/local/bin/gtk-config

I then get this when I do root joev:/home/joev/stuff/gimp-1.2.1 > set:

 _=GTK_CONFIG=/usr/local/bin
 _=GTK_CONFIG=/usr/local/bin/gtk-config
 
Then run ./configure and get same error. Am I setting the enviroment variable wrong? How do I fix this?

Thanks
Joe