strange issue with cron.daily

[Francesco Acchiappati]

Hello everyone,
i'm experiencing a strange issue everytime the crondaily runs the 
spamassassin script for updating.

the error returned to me by cron daily is the following:

run-parts: /etc/cron.daily/spamassassin exited with return code 25

I've tried to search on this list archive and also on the web for a 
solution but with no luck, can anyone give me an hint about what the 
return code 25 is supposed to mean?

thanks in advice.
Francesco