linking in code in ns (fwd)

[Tor Hval <thval@jungle.bt.co.uk>]

I am trying to integrate some code into ns running on a x86 FreeBSD box
using gcc version 2.95.1 to compile. 
Unfortunately I end up with some linking problems from quite a few time,
there are only two different symbols that are the problem(but they are
repeated many times), the undefined references are to:
 `TclClass type_info function'
and  `TclClass type_info node'
 
Can anybody help me out with these?

Thanks
Tor Hval