Microsoft Exchange mailboxes accessed via Outlook Web
Access (usign WebDav ) do not support LOCK's, so I've
added a "nolocks=1" support on the options.
Also I noted that there is no option to ask for user
credentials, and thus they appear on a simple process
list, so I added support for an "askauth=1" option also.
There are probably better ways to deal with this, but i
just wanted it to work right now.