g77 and Debian Squeeze

Dear Fluka List,

I hope someone can help me with this problem.
Under Debian Lenny, it was still possible to install g77 from old etch
repositories and to compile Fluka.
Debian Squeeze, which will become the stable version soon, still
accepts the necessary g77 packages, but Fluka does not
compile anymore (ok, actually, it's a linker error):

/usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux-gnu/3.4.6/../../../libfrtbegin.a when
searching for -lfrtbegin
/usr/bin/ld: skipping incompatible /usr/lib/libfrtbegin.a when searching for -lfrtbegin
/usr/bin/ld: cannot find -lfrtbegin

Does anybody have a solution for this problem?

I'm using Debian Squeeze amd64 on a 64 bit machine:
Linux xxxxxx 2.6.32-3-amd64 #1 SMP Wed Feb 24 18:07:42 UTC 2010 x86_64 GNU/Linux

I saw that already 2008 in a discussion someone was announcing to modify
the sources so that Fluka can be compiled with gfortran.
Has there been some progress on this field?

Thanks a lot for your help!

Cheers,
Andreas