Version: kmail 1.13.6

I upgraded to KDE 4.7 (Kubuntu). If I'm not mistaken, the version of kmail was not changed by this upgrade.
Now, it is impossible to move or copy mails between accounts anymore.

Error while uploading message
Could not upload the message dated Yesterday 23:56:31 from xxxx xxxxx <xxx@xxxx.xxx> with subject "blablababla" to the server.
The destination folder was: Kolab Server Mail/inbox/list.ubuntu-server.
The server reported:
Missing required argument to Append command

If you open KMail > Help > About KMail, what version of KMail do you have?

I'm also getting this error. I'm running Kmail 1.13.7 (on KDE 4.7.2) on Debian unstable/experimental. I run my own Cyrus IMAP server which was not changed when i upgraded my laptop.

Looks like the issue has been resolved with KMail 1.13.7 on KDE 4.7.4.