HMR-How to change values under the Proxy-Authorization Register Header

Hi Fellows,

I would like you can help to identify where I can find information what are the type that I have to define in my element-rule to any of the values under the Proxy-Authorization header?

There is any HMR document with this? 

Proxy-Authorization: Digest username="555-1234", realm="Realm", nonce="N2UwNWY3NDRjZGEwNzI2MDE4ODNlYWJh", qop=auth, cnonce="JVVE1Lgv", nc=00000001, uri="sip:domain1.com:5060", response="f96e5f

      Authentication Scheme: Digest

      Username: "555-1234"

      Realm: "Realm"

      Nonce Value: "N2UwNWY3NDRjZGEwNzI2MDE4ODNlYWJh"

      QOP: auth

      CNonce Value: "JVVE1Lgv"

      Nonce Count: 00000001

      Authentication URI: "sip:domain1.com:5060"

      Digest Authentication Response: "f96e5f00cdb6"