I have experienced some interesting results while posting. Some times while useing "[UR][/URL]" pairs they get converted to "[A][/A]" pairs. Particulary if nesting Urls in '" pairs. What's up with that?
I haven't ever observed this, or been able to replicate the problem. Can you show a post in whihc it's happened? If necessary you can e-mail me the text you submit, since it's hard to display it here without the tags getting interpreted.