I have an odd problem that has been reported by a few users over the past few weeks. Seems that folders in their mail files are winding up in new locations (either moving from subfolders to become top-level folders, or from top-level folders to subfolders of new “Untitled” folders). I was inclined to write this off as user error the first time, but there have been enough reports to take this seriously.
All of the clients are using 6.0.2CF1 client, and their server has been upgraded from 6.0.1 to 6.0.2CF2 about two weeks ago.
I’ve actually had this happen to me, upon occasion. It turns out that it was s SUT (Stupid User Trick). I was dragging a message to a folder for filing. Apparently, I released the message and grabbed the folder (not realizing it, of course) and continued to move the mouse. This had the effect of moving the folder, just as you described it.