Help: Trouble updating Slink -> Potato

[Berthold Cogel <cogel@rrz.uni-koeln.de>]

I NEED HELP!!!

Each time I try to update Debian Slink, the process is terminated
because of some problems with the perl packages. The update of perl
fails because perl-base is not configured. 
It doesn't matter how I update the system. It's the same problem with
'apt-get dist-upgrade', deselect-apt, via Internet or cdrom. 
After this bug happens, the whole system is in an undefinded state so
that I have to restore my backup.
Is there anybody, who can help?

Thanks in advance

Berthold Cogel