Fatal Error in config file?

[Mike Allen]

After configuration of Cyrus 2.1.12, there appears a Fatal Error after
startup/reboot.  The error is:

     imaps[186] Fatal Error: defaultpartition option contains
     non-alphanumeric character.

There are no non-alphanumeric characters anywhere in the config file
(imapd.conf).

I even re-created imapd.conf by typing all the options by hand and I
still get this error.

Can someone point me where to start debugging this error?  Any help would
be appreciated.

Mike Allen