Ubuntu tcl/tk problems

Error in firstlib(which.lib.loc, package) :
  Tcl/Tk support is not available on this system
Error : package 'tcltk' could not be loaded

Ubuntu 9.10
I have both the 8.5 and 8.4 tcl and tk regular and dev libraries
installed.  I need both of these because some of my GIS software
requires the 8.4 libraries.  Should I remove the 8.5 libraries, or ...

All help is greatly appreciated!
regards,

Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods.  We are mammals, and have not exhausted the
annoying little problems of being mammals.

								-K. Mullis