Решил сделать DialIn server на MPD. Установил на FreeBSD5.5 из портов настроил

# cat mpd.conf
#################################################################
#
#       MPD configuration file
#
# This file defines the configuration for mpd: what the
# bundles are, what the links are in those bundles, how
# the interface should be configured, various PPP parameters,
# etc. It contains commands just as you would type them
# in at the console. A blank line ends an entry. Lines
# starting with a "#" are comments and get completely
# ignored.
#
# $Id: mpd.conf.sample,v 1.18 2005/09/18 12:49:49 mbretter Exp $
#
#################################################################

startup:
        # enable TCP-Wrapper (hosts_access(5)) to block unfriendly clients
        set global enable tcp-wrapper
        # configure the console
        set console port 5005
        set console ip 192.168.1.2
        set console user admin superadmin
        set console open

default:
        load dialin0
        load dialin1

dialin0:
        new -i ng0 dialin0 usr0
        set iface addrs 192.168.1.5 192.168.2.5
        set ipcp ranges 192.168.1.5/32 192.168.2.5/32
        load dialin_standart

dialin1:
        new -i ng1 dialin1 usr1
        set iface addrs 192.168.1.6 192.168.2.6
        set ipcp ranges 192.168.1.5/32 192.168.2.5/32
        load dialin_standart

dialin_standart:
        set iface idle 900
        set iface session 0
        set ipcp yes vjcomp
        set ipcp dns 192.168.1.1
        set iface enable proxy-arp
        set link enable chap-md5
        set link disable pap chap-msv1 chap-msv2
        set link deny chap pap
        set link yes acfcomp protocomp
        set modem idle-script AnswerCall

# cat mpd.links

usr0:
        set link type modem
        set modem device /dev/cuaa0
        set modem var $DialPrefix "DT"

usr1:
        set link type modem
        set modem device /dev/cuaa1
        set modem var $DialPrefix "DT"

Все заработало но есть проблема при соединении клиента и вводе неправильного пароля  
сетевой интерфейс блокируется, т.е. модем берет и сразу бросает трубку. После рестарта mpd все востанавливаетя.