Problems with SpamAssassin - new year bug?

Hello, it seems that a lot of legit mails are going [SPAM], but what worries me most is that it marks as spam and fly to Usermin spam directory exactly the mails sent between the domains hosted on the same server with a score of 9.7!

X-Spam-Flag: YES
X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on ns1.i-ware.ro
X-Spam-Level: *********
X-Spam-Status: Yes, score=9.7 required=5.0 tests=FH_DATE_PAST_20XX,    HTML_MESSAGE,RCVD_IN_BL_SPAMCOP_NET,RCVD_IN_SORBS_WEB,RCVD_IN_XBL,RDNS_NONE    autolearn=no version=3.2.5
X-Spam-Report: *  3.4 FH_DATE_PAST_20XX The date is grossly in the future.    *  2.9 RCVD_IN_XBL RBL: Received via a relay in Spamhaus XBL    *      [xxxxxx listed in zen.spamhaus.org]    *  2.2 RCVD_IN_BL_SPAMCOP_NET RBL: Received via a relay in bl.spamcop.net    *      [Blocked - see <http://www.spamcop.net/bl.shtml?xxxxxx>]    *  0.0 HTML_MESSAGE BODY: HTML included in message    *  1.1 RCVD_IN_SORBS_WEB RBL: SORBS: sender is a abuseable web server    *      [xxxxxx listed in dnsbl.sorbs.net]    *  0.1 RDNS_NONE Delivered to trusted network by a host with no rDNS

The problem is not with the ip or anything else as one may believe, but with "3.4 FH_DATE_PAST_20XX The date is grossly in the future." It seems it's a bug: https://issues.apache.org/SpamAssassin/show_bug.cgi?id=6269 And this is happening only to the 2010 emails - these are strictly related and never had this kind a problem in 2009.

We have a standard installation on CentOS 5.4 x64, via the Virtualmin Pro installer; all the updates presented by Virtualmin on the first page have been applied...

So what can we do? I mean except adding my own domains to my own server as trusted senders :)

Thank you. And A Happy New Year!