No sure way to tell.
The Zone has an "HTML Preview" button at the top of the reply window that almost always shows how your message is going to look after posting. I don't know if it works or shows up on all browsers (I use Internet Explorer). Try it, and most hotlink jamming gimmicks will show up at this point.
I do remember a few cases where it shows up great in the preview, but turns into a red X in the post.