+ # We do not raise an error if the user doesn't exist. This is due to
+ # an unfortunate problem with the "user exists" check in AgenDAV.
+ # The AgenDAV "shares" table is not tied directly to a username, so
+ # we are forced to use a regexp match to decide what rows to delete
+ # from that table. We do so regardless of whether or not the username
+ # exists in the "prefs" table, because that table stores only non-
+ # default preferences -- not all users' preferences.
+ #