spamassassin and bayes filter after sarge upgrade

[Brian Walker <bfwalker@net-yan.com>]

Greetings all,

my wonderfully smooth upgrade from woody to sarge last night is showing
the first glitches. Spamassassin had been installed from source
previously. The upgrade appeared fine, and indeed spam is being caught and
marked.

When I try to teach spamassassin based on "missed spam" I get the
following error:

brian@debian:~$ sa-learn --mbox --spam /home/brian/Mail/MissedSpam
Cannot open bayes databases /home/brian/.spamassassin/bayes_*R/O: tie
failed: 
Cannot open bayes databases /home/brian/.spamassassin/bayes_*R/O:
tie failed: File exists
Learned from 0 message(s) (10 message(s) examined).

My local.cf file in /home/brian/spamassassin/user_preferences contains no
mention of bayeslocation (set up previously did not require it) and the
bayes files are Bayes_journal bayes_toks and bayes_seen. 

Google is empty of references, and the spamassassin manuals have proved a
dry tap so far. Thoughts?

All the best,

Brian