<p>That is the Maildir format. Cur is the "seen messages" (not seen by the user, but seen by the user's MUA. The new directory holds the one the MUA hasn't seen yet. The messages may have multiple hardlinks for example if they have been moved or deleted and not yet expunged.</p>
<p>For the most part, you can just treat the directory tree as a message database. One complete message is stored in one file, and the name of the file contains the IMAP flags applicable to it. It should be possible to read them in one file at a time and write them back out as an mbox format file. You need to create the mbox "from" line at the start of each message, and add > characters to the word "from" that begins the line of a message if one isn't already there... but I do not believe that they need any additional transformation.</p>
<p>--<br>
Sent from my G2 running CyanogenMod!<br>
That is, a phone. :)</p>
<div class="gmail_quote">On Nov 16, 2010 4:14 PM, "Lightner, Jeff" <<a href="mailto:jlightner@water.com">jlightner@water.com</a>> wrote:<br type="attribution"></div>