code: function(handler, cbvalidate) {
          var req   = handler.httpRequest;
          var A2    = req.method + ":" + this.digestParts["uri"];
          var self  = this;
  
          if (this.digestParts["qop"] == "auth-int") {
              // Making sure we support this qop value
              if (!(this.qop & QOP_AUTHINT))
                  return cbvalidate(false);
              // We need to add an md5 of the entire request body to the A2 part of the hash
              handler.getRequestBody("utf8", null, false, function(noop, body) {
                  A2 += ":" + Util.createHash(body);
                  afterBody();
              });
          }
          else {
              // We need to make sure we support this qop value
              if (!(this.qop & QOP_AUTH))
                  return cbvalidate(false);
              afterBody();
          }
  
          function afterBody() {
              A2 = Util.createHash(A2);
  
              var validResponse = Util.createHash(self.A1 + ":" + self.digestParts["nonce"] + ":"
                  + self.digestParts["nc"] + ":" + self.digestParts["cnonce"] + ":"
                  + self.digestParts["qop"] + ":" + A2);
  
              cbvalidate(self.digestParts["response"] == validResponse);
          }
      }
docs: Validates the digest challenge
  
  @return bool