You are missing the local.cf or any similar local config. MailScanner puts a mailscanner.cf symlink there that points to /etc/MailScanner/spamassassin.prefs.conf The symlink seems to have been deleted.
I usually do it a bit different. I maintain my own local.cf in /etc/mail/spamassassin and touch an empty mailscanner.cf file there, so that MailScanner is satisfied. Kai -- Get your web at Conactive Internet Services: http://www.conactive.com