I have recently upgraded Zimbra-6.0.10(OSS) to Zimbra-7 (GA). Everything went smoothly except SPAM filters. The zimbra.log shows all the services are working perfectly. However, the spam filters doesn't seem to work properly and the *show original* doesn't display any of the SPAM headers.

I tried by sending the GTUBE and it is also directly delivered in inbox without any spam headers.

How can I troubleshoot this issue?

thanks in advance.