Indexing MSFT Outlook/Exchange mail...or really, URLs that refer to Outlook

["Spencer, Dave" <da...@lumos.com>]

It's not hard to use JavaMail to go to an IMAP server and go thru
all mail msgs and feed them to Lucene - I have a proof of concept 
that works fine.
 
What I can't figure out is if there's some URL syntax that tells IE to
tell Outlook to pull up a selected mail msg. 
 
Goal is to have a web page of search results with appropriate URLs
so that the mail client will go to the selected mail msg.
 
Haven't found anything on the web, msdn, or whatnot.
 
Sometimes when I print I do briefly see "outlook:" in the printer status
window
so maybe that's a clue.
 
Ideally the syntax will have some unique identifier of the msg in it.
 
Does anyone know of the MSFT/Outlook/Exchange URL formats or where 
(in the registery?) these would be defined?