pop3: If UIDL using %f/%m/%g can't be fetched, mention pop3_uidl_format in error message.
pop3: If UIDL using %f/%m/%g can't be fetched, mention pop3_uidl_format in error message.

dscho/dovecot,dscho/dovecot,dscho/dovecot,dscho/dovecot,dscho/dovecot