IMAP MOVE command not being used? (server supports it)

Question

I created an IMAP log, to see whether TB was using the IMAP "MOVE" extension. Despite the fact that my IMAP server does appear to support it, I can't see any MOVE commands in my protocol log. The only times the string "MOVE" appears in log is the CAPABILITY response from the server. FWIW, here is the capability string:
[CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS SPECIAL-USE BINARY MOVE NAMESPACE QUOTA]
Note that I moved a message BETWEEN mailboxes, if that makes a difference. (if it only works intra-mailbox, then I can't make use of it)
What exactly should I see in my protocol log, if TB is using the MOVE command?
Environmemt: TB 31.0, Windows 8.1-64, Dovecot IMAP server

Answer 1

Thanks, but before I do that, I don't mind asking for help elsewhere, perhaps on the Dovecot list or something. I notice that an INTRA-mailbox move does go significantly faster, and I see a "moved messages" status message down the bottom, too. (haven't checked the log yet, but I strongly suspect it is using the IMAP MOVE extension for this operation)
Postbox behaves the same as Thunderbird - inter-mailbox moves are very slow - it is obvious that it is manually moving the messages. (and likewise, intra-mb moves are rapid)
I kind of suspect that it's just not going to work between mailboxes, despite what the RFC says. If I find out anything, or file a bug report, I will indeed report back.