[Dovecot] Subfolders not listed in Dovecot-1.2.2 with listescape

[Petter Urkedal]

After upgrading to Dovecot-1.2.2 from 1.1* subfolders disappeared,
though it was possible to access them directly, e.g. with
"mutt -f =lists/dovecot".  The problem only occurs if the listescape
plugin is enabled.  Some relevant bits from the configuration:

namespace private {  # The only namespace.
    separator = /
    prefix = 
    inbox = yes
}
protocol imap {
    mail_plugins = fts fts_squat listescape
}