Tkx Cannot Find Various img Packages

[E.R. Uber]

I am using Tkx and doing a
      Tkx::package_require('img::gif')

which yields a "can't find package" error.
The same is true for 'img::jpeg' and 'img::bmp', in fact the ONLY img
packages that are successful found are 'img::png', 'img::ico' and 'img::xpm'

I am using ActivePerl 5.10 and ActiveTcl 8.5 on XP, but I get the same
errors under Fedora 9.

I see all the img packages in the tcl installation but I am wondering why
via Perl/Tkx I am only able to find some of them but not all of them.

Thanks,
E.R.