Okay, let me modify my suggestion, then: if you can detect where the displayed text for a link is a URL, and the domain name in that URL does not match the domain name in the href, then it might be useful.Does that seem more possible?
Nope. Just look at millions of things sent by constantcontact.com where they add their tracking links to the newsletter content.
Sorry to be negative but I really don't think you are going to find this to be an indication of spam or ham.
