Can I view my Microsoft Exchange Online Archive via Davmail in Thunderbird

I have successfully set up Davmail on Ubuntu 14 and am able to read, receive and send mail on my Exchange account in Thunderbird. This page was a big help!: http://nknu.net/ubuntu-14-04-exchange-configuration-thunderbird-pidgin/ I set the account up as IMAP, so I can also browse folders. One thing I can't seem to do is subscribe to or otherwise access the "Online Archive" - a copy of my Inbox and subfolders for all mail more than a year old (my IT department's policy). Davmail release notes say that this is possible but I can't find any guides on how to view this archive folder in Thunderbird, or any other mail clients. Can anyone suggest what to do or what to read? Cheers, Ryan