tricky subject lines from spammers

[fyd]

I have managed to tackle spam to a good extend with a score of 2.8. But these days the spammers are using tricky subject lines. I have no idea how to curb them, neither the subject line nor the contents show signs of spam. See these subjects ..

"Ad u.lt, P. ic. ture"
"S C,H 0,O L Gl _RLS PO R _N"
"B L.0, W_ J OB"

the contents have links that are just some random letters joined to form a domain. Shit.

The spam score for these mails are like 1.8, 1.3, 2.35 etc. So they are nowhere near my score of 2.8 (which I think is a bit strict check). I really need to beat these guys.

Now is it true that my only chance is to move these mails to Junk and thereby train zimbra to detect them as spam the next time?

I could bring the score further down but that will affect my legitimate mails.

Out of desperation I had to pick out source mail ids and block them in salocal.conf.in but that is not practical. I need to make zimbra more clever and bring out her best.

Please share if any one had to face this, your thoughts on how it can be improved. Hoping for a quick response, thank you.

[phoenix]

You really shouldn't be seeing this sort of spam (at least not much of it) in your Inbox. What changes have you made to the anti-spam system (if any)? What's your kill/tag percentages? Is DSPAM activated and working? Does sending these messages to the Junk folder train your system? Which RBLs are you using? Are these emails not getting categorised as spam? What information do the the headers show about the source of this email?