EAP-TLS obtaining certificates email

Hi, I have used an outside certificate authority and have few clients that have the certicifates' subject similar to: E = user-name@domain.tld CN = Some-constant-text CN is constant on all certificates. Freeradius gets the User-name attribute set to CN. Any way to substitute the User-name attribute with the email? Or have it al least logged with other attributes in detailed log? Cheers, Piotr Janusz.