Comment 108 for bug 308181

Andre,
a) This is offtopic here, because this bug is specifically about DNS, and the MS protocol is based on XML. (Outlook can also look up DNS SRV records, but only when explicitly enabled by pref.)
b) Microsoft itself dropped the protocol that Exchange 2007 uses, because they didn't like it anymore. Exchange 2010 uses a different, SOAP-based protocol.
c) Both protocols require the user not only to know the username in advance, but also to authenticate to Exchange, before the server returns any configuration (even though it's just hostnames etc.). I find myself often not knowing how exactly my username is expected (with @ or //, with or without domain, email address or other username), so that alone is a no-go. We go from only realname, email address and password.

That the XML-based protocol has already been implemented in Thunderbird 3.
This bug is about finding servers via DNS.