where is tcl?

[surya]

Hello all,

Recently I compiled network simulator (nam and nam with GUI) and
./configure reports tcl installation is incomplete or can not find it 
automatically.

I try ./configure --with-tcl=/usr/lib/  but no luck.

Where is tcl package(s) with (all) associated libraries?
I suspect they are inside "Kernel Development" under "Add/Remove 
Applications". (???)
(I can see why Debian users are very fond of their apt.)

Many thanks in advance.
surya
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