Alright, because I refuse to admit defeat I did the next best thing which will still save you time & effort.
It's a li'l script I whipped up that will convert your HTML code so that you can paste it into the post and have it appear correct.
Just upload it to your threads folder and bookmark it, or better yet, make it a javascript popup and place the link in your addpost template so it'll be nice and handy.
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