As Donny pointed out, you can get most of the information you want from the mail logs. Whether the message was rejected due to reputation filtering, stopped by a specific policy setting, dropped as a virus, or anything else, all the details will be in the mail logs.
But there is one thing you won't get that way. If IronPort Anti-Spam (known in the logs as CASE, the Context Adaptive Scanning Engine), considers a message to be spam, then you won't be able to find out what rules triggered this verdict. This information is not disclosed, to prevent spammers from using it to learn how to adapt their messages. The fact that CASE decided that the message was spam is noted in the logs, just not what particular rules led to this decision.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...