Hi
I want to change authentication pap to chap. The users with clear passwords are in ldap server. The error is :

rlm_ldap: - authenticate
rlm_ldap: Attribute "User-Password" is required for authentication. Cannot use "CHAP-Password".
Login incorrect (rlm_chap: Clear text password not available):

I saw the problem in faq but I didn't find what is my mistake. The config is:
in users :

DEFAULT Client-IP-Address == 10.10.10.2 , Auth-Type := Vpn, Autz-Type := Vpn, Post-Auth-Type := Vpn, Session-type := Vpn

in radius.conf:
ldap ldap-Vpn{
               ....
                password_attribute = userPassword
                password_header = "{clear}"

        }
authorize {
chap
Autz-Type Vpn{
                ldap-Vpn
                chap
                  }
}

authenticate {
Auth-Type CHAP {
                chap
        }
Auth-Type Vpn{
                chap
               ldap-Vpn

      }

}

....
what is my mistake? should I do any other config or change in ldap.attrmap?