A tool written in PHP which allows you to migrate OR archive your e-mail from one IMAP server to another. This becomes especially useful when one of the IMAP servers is non-UNIX (ie Exchange Server).
I make a fork in this project, it is in SF named as PHP IMAP Migration Tool, there are so many fixes that may not be problematic like this project, since it is not updated for 9 years.
Problematic. I've spent hours to make it work and alas it does the job. Today Apr 21, 2012 it's nearly a year after the last update. If you do not want to update it, please leave it to me.