Spam Assassin Not Assigning Scores

[librun]

I've noticed that spam assassin periodically stops assigning scores to messages, which results in headers that look like this:

X-Spam-Status: No, score=
X-Spam-Score:
X-Spam-Bar:
X-Spam-Flag: NO

Of course it's supposed to look more like this:

X-Spam-Status: Yes, score=17.3
X-Spam-Score: 173
X-Spam-Bar: +++++++++++++++++
X-Spam-Flag: YES

I read on other forums that spam assassin stops if the server is getting hit with too much spam (http://forums.jumba.com.au/showthread.php?t=6193). Does anyone know if this is true? If I crontab a periodic /etc/init.d/spamd restart will this fix the problem?

Thanks,

librun

 

[librun]

Actually there is no /etc/init.d/spam.d, however there is a /scripts/restartsrv_spamd