ldap machine account auth tutorial

[cd]

hello
I'm looking for a toturial ti authenticate XP machines accounts (ldap backend) on boot with freeradius


here a computer LDAP entry 
dn: uid=pc-42ee2079$,ou=computer,ou=ressources,ou=test,o=coin,c=fr
objectClass: top
objectClass: account
objectClass: posixAccount
objectClass: sambaSamAccount
cn: pc-42ee2079$
uid: pc-42ee2079$
uidNumber: 10006
gidNumber: 515
homeDirectory: /dev/null
loginShell: /bin/false
description: Computer
gecos: Computer
structuralObjectClass: account
sambaSID: S-1-5-21-902432509-630223792-3260868441-1000
displayName: pc-42EE2079$
sambaAcctFlags: [W ]
sambaNTPassword: 2A8BBB29BEF5F91B02AF687290ADB4F7
sambaPwdLastSet: 1262772595



should I put in ldap.attr
checkItem Cleartext-Password sambaNTPassword


or should I put in modules/ldap
password_attribute = sambaNTPassword


What must I put in users file, if I want that assign VLAN If authentification succeed ?

thanks