Your forums do. But the emails do not, to keep them from repeating themselves indefinately.
As I mentioned, I did it this way til I could determine how I would assign prefixes for new threads from emails
Most likely the next version will support thread prefixes. It entirely depends on how severe rewriting the regexs will be.
If they take a long time then I'll release 2.3 without the thread prefix support and work on that for 2.4. As right now, the regexs take priority
But I will definately have support for thread prefixes soon! As I use those as well on my forums