hmm ... just took another look at the package descriptions. It seems
that the problem is libg2c0. How come this still depends on an older
version of gcc-3.4.6? I link some of my programs with some FORTRAN
libraries and need libg2c0. So for now I have been keeping gcc-3.4 at
its older version during every upgrade. So, what's the deal with libg2c0?
Looks like support for the old legacy compilers is reaching its end of
life:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=473647
You might consider transitioning to something newer, if possible.