Email filtering using regex

[Alex1200GS]

Hello all,

I am receiving a considerable amount of spam lately, although I have SpamAssassin on and a lengthy list of manual filters in place. The new type of spam does not have a wording pattern that I can use to create a filter; on the other hand, it contains max 2 lines of sensible text and a link. Here's a real-life example:

From: Jeff <[email protected]>
To: me
Subject: Paris Hilton Tosses Dwarf On The Street
Date: Mon, 21 Jul 2008 21:21:11 +0200 (22:21 EEST)

Stock Markets Close As Global Earth World Planet International Buys All Shares
http://candou.com.br/viewmovie.html

or

From: Joffrey <[email protected]>
To: me
Subject: Barry Bonds convicted of perjury
Date: Mon, 21 Jul 2008 09:10:04 +0200 (10:10 EEST)

Man loses arm to save 3m shark http://sbm.it/start.html

I suppose what I need is a script (regex?) filtering off all messages that are shorter than XX characters and contain a link. Any help to that direction would be highly appreciated.

Thanks,

Alex