@bes I don't think auto-checking email addresses for XMPP availability is a very good idea. But integration where the mail and web clients properly parse xmpp:mmn@hethane.se and turn it into a link which my !XMPP cilent can be started with to request authorization or create a new message - that's neat functionality.

(there are privacy reasons why not to auto-check email addresses for XMPP server stuff, but I would rather argue that it shouldn't be done because having an email that's also a JID is by no means a guarantee that the remote party actually uses that account - which would lead to tons of false positive roster entries).