compiling tcltkgrass

[WIM MEES]

Hello,

I've downloaded tcltkgrass.tar.Z and tried
to compile it. In the Makefile there are
directories like /mnt/develop/tcltk/tk3.6
and /mnt/develop/tcltk/tcl7.3.

Since I'm not familiar with tcltk (in fact
what does it stand for ?) it can only guess
but it appears to me that I'm missing some
kind of tcltk library.

Can anyone tell me where to find it ?

Wim