Spamassassin and outgoing score

[JN]

Our spam filter doesn't detect outgoing spam correctly:

Dec 8 21:51:47 filter-server amavis[26276]: (26276-10-2) Passed CLEAN, [XXX.XXX.XXX.XXX] [XXX.XXX.XXX.XXX] <sen...@domain.com> -> <recip...@aol.com>,<recip...@aol.com>,<recip...@aol.com>,<recip...@aol.com>, Message-ID: <358b1ca257f4$254f15bf$21291243$@domain.com>, mail_id: B59yEbiUvXeE, Hits: 3.3, size: 4365, queued_as: E5AEA21BE4C, 5156 ms

So the mail is checked by Spamassassin and the score is 3.3

Recipient server thinks it spam and blocks mails coming from us. So the mail stays in our mailq. Now, if I test that mail with spamassassin -t, I get totally different score:

# spamassassin -t < /var/spool/postfix/deferred/E/E5AEA21BE4C


Content analysis details: (9.4 points, 5.0 required)

pts rule name description
---- ---------------------- --------------------------------------------------
0.0 MISSING_MID Missing Message-Id: header
0.0 MISSING_DATE Missing Date: header
-0.0 NO_RELAYS Informational: message was not relayed via SMTP
2.5 MISSING_HB_SEP Missing blank line between message header and body
2.5 HEAD_LONG Message headers are very long
1.6 MISSING_HEADERS Missing To: header
1.5 NULL_IN_BODY FULL: Message has NUL (ASCII 0) byte in message
1.3 MISSING_SUBJECT Missing Subject: header
-0.0 NO_RECEIVED Informational: message has no Received headers
0.0 NO_HEADERS_MESSAGE Message appears to be missing most RFC-822 headers


Why is this happening? We have a bit of a problem with outgoing spam..

-JN