>>Apr  5 18:07:59 localhost pppd[3294]: rc_avpair_gen: received unknown attribute 85 of
>>length 4: 0x0000003C
>
>попробуй добавить в "/etc/radiusclient/dictionary" строчку "ATTRIBUTE      
>Acct-Interim-Interval   85      integer"

Ошибка:
Apr  5 18:07:59 localhost pppd[3294]: rc_avpair_gen: received unknown attribute 85 of length 4: 0x0000003C
из логов ушла, но авторизация по прежнему не проходит.
Появились следующие ошибки в логах:

Sun Apr  6 12:28:09 2008 : Auth: rlm_nibs (rlm_nibs_authenticate): Zero length password not permitted for user `chernobaev' [127.0.0.1:0] |192.168.104.5|
Sun Apr  6 12:28:09 2008 : Auth: Login incorrect: [chernobaev/<no User-Password attribute>] (from client localhost port 0 cli 192.168.104.5)

Apr  6 12:28:09 localhost pppd[2959]: Plugin radius.so loaded.
Apr  6 12:28:09 localhost pppd[2959]: RADIUS plugin initialized.
Apr  6 12:28:09 localhost pppd[2959]: Plugin /usr/lib/pptpd/pptpd-logwtmp.so loaded.
Apr  6 12:28:09 localhost pppd[2959]: pppd 2.4.4 started by root, uid 0
Apr  6 12:28:09 localhost pppd[2959]: Using interface ppp0
Apr  6 12:28:09 localhost pppd[2959]: Connect: ppp0 <--> /dev/pts/2
Apr  6 12:28:19 localhost pppd[2959]: Peer chernobaev failed CHAP authentication
Apr  6 12:28:19 localhost pppd[2959]: Connection terminated.
Apr  6 12:28:19 localhost pppd[2959]: Exit.
Выкладываю конфиги
//===========================================================================
pptpd:
#ppp /usr/sbin/pppd
speed 115200
option /etc/ppp/pptpd-options

debug

# stimeout 10
#noipparam
logwtmp
bcrelay eth1
localip 192.168.104.1
remoteip 192.168.20.10-23
//============================================================================
PPTPD-OPTIONS:

ppptp-options:
name pptpd
plugin radius.so
plugin radattr.so
#chapms-strip-domain

#require-pap
#refuse-chap
require-mschap
require-mschap-v2
require-mppe-128
# }}}
ms-dns 192.168.104.1
#ms-dns 10.0.0.2

#ms-wins 10.0.0.3
#ms-wins 10.0.0.4

proxyarp

nodefaultroute

# Logging

#debug

#dump

# Miscellaneous

lock

# Disable BSD-Compress compression
nobsdcomp
nodeflate
novj
novjccomp
//==================================================================================
radiusd.conf:

prefix = /usr
exec_prefix = /usr
sysconfdir = /etc
localstatedir = /var
sbindir = ${exec_prefix}/sbin
logdir = /var/log/freeradius
raddbdir = /etc/freeradius
radacctdir = ${logdir}/radacct

confdir = ${raddbdir}
run_dir = ${localstatedir}/run/freeradius
log_file = ${logdir}/radius.log
libdir = /usr/lib/freeradius
pidfile = ${run_dir}/freeradius.pid
user = freerad
group = freerad
max_request_time = 30
delete_blocked_requests = no
cleanup_delay = 5
max_requests = 1024
bind_address = *
port = 0
hostname_lookups = no
allow_core_dumps = no
regular_expressions    = yes
extended_expressions    = yes
log_stripped_names = no
log_auth = yes
log_auth_badpass = yes
log_auth_goodpass = yes
usercollide = no
lower_user = no
lower_pass = no
nospace_user = no
nospace_pass = no
checkrad = ${sbindir}/checkrad
security {
    max_attributes = 200
        reject_delay = 1
        status_server = no
}

proxy_requests  = yes
$INCLUDE  ${confdir}/proxy.conf

$INCLUDE  ${confdir}/clients.conf
snmp    = no
$INCLUDE  ${confdir}/snmp.conf
thread pool {
    start_servers = 5
    max_servers = 32
    min_spare_servers = 3
    max_spare_servers = 10
    max_requests_per_server = 0
}
modules {
    pap {
        encryption_scheme = crypt
    }
    chap {
        authtype = CHAP
    }
    pam {
        pam_auth = radiusd
    }
    unix {
        cache = no
        cache_reload = 600
        shadow = /etc/shadow
        radwtmp = ${logdir}/radwtmp
    }
$INCLUDE ${confdir}/eap.conf
    mschap {
        authtype = MS-CHAP
        use_mppe = yes
        require_encryption = yes
        require_strong = yes
        #ntlm_auth = "/path/to/ntlm_auth --request-nt-key --username=%{Stripped-User-Name:-%{User-Name:-None}} --challenge=%{mschap:Challenge:-00} --nt-response=%{mschap:NT-Response:-00}"
    }
ldap {
        server = "ldap.your.domain"
        # identity = "cn=admin,o=My Org,c=UA"
        # password = mypass
        basedn = "o=My Org,c=UA"
        filter = "(uid=%{Stripped-User-Name:-%{User-Name}})"
        start_tls = no
        access_attr = "dialupAccess"
        dictionary_mapping = ${raddbdir}/ldap.attrmap

        ldap_connections_number = 5
        timeout = 4
        timelimit = 3
        net_timeout = 1
        # compare_check_items = yes
        # do_xlat = yes
        # access_attr_used_for_allow = yes
    }

    realm IPASS {
        format = prefix
        delimiter = "/"
        ignore_default = no
        ignore_null = no
    }
    realm suffix {
        format = suffix
        delimiter = "@"
        ignore_default = no
        ignore_null = no
    }
    realm realmpercent {
        format = suffix
        delimiter = "%"
        ignore_default = no
        ignore_null = no
    }
    realm ntdomain {
        format = prefix
        delimiter = "\\"
        ignore_default = no
        ignore_null = no
    }    
    checkval {
        # The attribute to look for in the request
        item-name = Calling-Station-Id

        # The attribute to look for in check items. Can be multi valued
        check-name = Calling-Station-Id

        # The data type. Can be
        # string,integer,ipaddr,date,abinary,octets
        data-type = string

        # If set to yes and we dont find the item-name attribute in the
        # request then we send back a reject
        # DEFAULT is no
        #notfound-reject = no
    }
    preprocess {
        huntgroups = ${confdir}/huntgroups
        hints = ${confdir}/hints
        with_ascend_hack = no
        ascend_channels_per_line = 23
        with_ntdomain_hack = no
        with_specialix_jetstream_hack = no
        with_cisco_vsa_hack = no
    }
    files {
        usersfile = ${confdir}/users
        acctusersfile = ${confdir}/acct_users
    }
    detail {
        detailfile = ${radacctdir}/%{Client-IP-Address}/detail
        detailperm = 0600
    }
    acct_unique {
        key = "User-Name, Acct-Session-Id, NAS-IP-Address, Client-IP-Address, NAS-Port"
    }
    #  NiBS Support
    $INCLUDE  ${confdir}/nibs.conf
    radutmp {
        filename = ${logdir}/radutmp
        username = %{User-Name}
        case_sensitive = yes
        check_with_nas = yes        
        perm = 0600
        callerid = "yes"
    }
    radutmp sradutmp {
        filename = ${logdir}/sradutmp
        perm = 0644
        callerid = "no"
    }
    attr_filter {
        attrsfile = ${confdir}/attrs
    }
    counter daily {
        filename = ${raddbdir}/db.daily
        key = User-Name
        count-attribute = Acct-Session-Time
        reset = daily
        counter-name = Daily-Session-Time
        check-name = Max-Daily-Session
        allowed-servicetype = Framed-User
        cache-size = 5000
    }
    always fail {
        rcode = fail
    }
    always reject {
        rcode = reject
    }
    always ok {
        rcode = ok
        simulcount = 0
        mpp = no
    }
    expr {
    }
    digest {
    }
    exec {
        wait = yes
        input_pairs = request
    }

    exec echo {
        wait = yes
        program = "/bin/echo %{User-Name}"
        input_pairs = request
        output_pairs = reply
        #packet_type = Access-Accept
    }
    ippool main_pool {
        range-start = 192.168.1.1
        range-stop = 192.168.3.254
        netmask = 255.255.255.0
        cache-size = 800
        session-db = ${raddbdir}/db.ippool
        ip-index = ${raddbdir}/db.ipindex
        override = no
        maximum-timeout = 0
    }
}

instantiate {
    exec
    expr
#    daily
}
authorize {
    preprocess
#    auth_log
    nibs
#    attr_filter
#    chap
    mschap
#    digest
#    IPASS
#    suffix
#    ntdomain
#    eap
#    files
#    sql
#    etc_smbpasswd
#    ldap
#    daily
#    checkval
}
authenticate {
    Auth-Type PAP {
        pap
    }
    Auth-Type CHAP {
        chap
    }
    Auth-Type MS-CHAP {
        mschap
    }
    Auth-Type NIBS {
        nibs
    }
}
preacct {
    preprocess
    acct_unique
#    IPASS
#    suffix
#    ntdomain
#    files
}

accounting {
    acct_unique
    detail
#    daily
#    unix
    radutmp
#    sradutmp
#    main_pool
#    sql
    nibs
#    pgsql-voip
}
session {
#    radutmp
#    sql
    # NiBS zap
    nibs
}
post-auth {
#    main_pool
#    reply_log
#    sql
    nibs
#    Post-Auth-Type REJECT {
#        insert-module-name-here
#    }

}
pre-proxy {
}
post-proxy {
    eap
}