Folders gone after upgrade from 2.0.16 to 2.1.9

[Alexander Czernay]

I've just upgraded my Cyrus-IMAP from 2.0.16 to 2.1.9. As I used 
--enable-fulldirhash on configure, I ran tools/rehash full after 
installation. That seemed to work and looked good (no errors). All 
worked well.

As a second step I upgraded to include SSL support for IMAP and POP. 
After that I couldn't access any IMAP folder anymore, even after 
resuming standard IMAP operations in my mail client.

I also can't create new folders. Well, I can create them, but the next 
time I start my mail-client, they're gone.

The logs suggest that Cyrus is still looking for the folder in the 
file-system rather than in the dbs. What have I done wrong?

Thanks for any help

Alexander