I am also caught in the "Catch 22" of trying to upgrade to modutils. As I recall the sequence was that I installed a new system with the dummy version of modules (2.1.x) in unstable but there was no companion modutils package at the time and I could not manipulate modules. I then backed out to the version 2.0.0-15 of modules in the stable directory. Now I can't remove the old modules and hence I can't upgrade to modutils.
I can no longer find the dummy version of modules to try to do the installation the proper way. Even trying to force the installation of modutils doesn't seem to work # dpkg --force-conflicts --install modutils_2.1.23-2.deb dpkg: considering removing modules in favour of modutils ... dpkg: yes, will remove modules in favour of modutils. (Reading database ... 17076 files and directories currently installed.) Unpacking modutils (from modutils_2.1.23-2.deb) ... Kernel was compiled with module support! Modules package cannot be removed! dpkg: error processing modutils_2.1.23-2.deb (--install): subprocess pre-removal script returned error exit status 1 Errors were encountered while processing: modutils_2.1.23-2.deb