The first thing to point out is that your Kill/Tag percentages are not set to the default, that's 75/33 respectively. I have mine set to 66/25 and see very little spam. It looks like your messages are not being checked for many rules, a typical message in my Junk folder would have the following tests:
Code:
X-DSPAM-Result: Spam
X-DSPAM-Confidence: 0.6480
X-DSPAM-Probability: 1.0000
X-DSPAM-Signature: 4801f0c4273521156014651
X-DSPAM-Factors: 15,
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: YES
X-Spam-Score: 13.053
X-Spam-Level: *************
X-Spam-Status: Yes, score=13.053 tagged_above=-10 required=5
tests=[BAYES_99=3.5, DSPAM_SPAM=1.5, HTML_MESSAGE=0.001,
RAZOR2_CF_RANGE_51_100=0.5, RAZOR2_CF_RANGE_E8_51_100=1.5,
RAZOR2_CHECK=0.5, SPF_SOFTFAIL=0.596, URIBL_BLACK=1.955,
URIBL_JP_SURBL=1.501, URIBL_OB_SURBL=1.5]
Have a look in the /opt/zimbra/conf/spamassassin folder and see if you've got all the .cf rules files in there, you should have about 110(ish) files. Do you update those files at all?
Have you made any modifications to the ant-spam/virus system by adding any RBLs, whitelists, SPF, Razor, PYZOR etc? If you have, what are they? I assume your spam/ham mailboxes are still there and are set, check them with:
Code:
zmprov gacf | grep SpamAccount