Steel Belted Radius LDAP + Active Directory :PAP password required for Bind

Hi!
I want to configure my SBR radius to authentificate user into Active Directory throught LDAP request. I don’t want use Domain\Groups any more.
I use the flexible Bind option :
– my first request bind to LDAP by administrator account and search in LDAP : OK
– the 2nd request bind as failed because “PAP password required for Bind”
I don’t mention %Password in my request section like user guide says.
It seems the Windows XP password don’t pass-trough to LDAP/Active Directory
Any ideas ?