Client Certificate Authetication

Hi!

I have a question. I'm from Spain, and here exists two main client certificates to autheticate a user: DNIe and FNMT.

I'm trying to make an iRule to autheticate against an LDAP with this certificates, using the default iRule _sys_auth_ssl_cc_ldap

As far as I know in this line

AUTH::cert_credential $tmm_auth_ssl_cc_ldap_sid [SSL::cert 0]

uses de subject field to make the authentication, but as example, eDNI cert stores de username in a field called serialnumber. It's possible to perform the authentication against the LDAP with this kind of cert?

Thanks in advance!