Hi, I have the same problem, not only on IMAP folders but on local ones too but I'm not sure it is an icedove bug. I've seen the same bug report on BSD and Fedora forums and it seems to be a bug in libgtk2.0.0 (version 2.10.7-1 in experimental) (see https://www.redhat.com/archives/fedora-list/2007-January/msg04036.html for example).
When I try to move a message from one folder to another, I get the error : Gtk-CRITICAL **: gtk_drag_get_data: assertion `GTK_IS_WIDGET (widget)' failed Jean-Jacques -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]