C# 使用WCF或WIF从PingFederate获取轻量级SSO令牌

我正在为PingFederate提供的演示设置使用WCF编写客户端，其方式与本文（）中所述的类似。 我的问题是，在第二步中，我需要将SAML令牌交换到SP上的轻量级SSO令牌。 从SP序列化响应时出现异常

ID3135: The element 'TokenType' with namespace 'http://docs.oasis-open.org/ws-sx/ws-trust/200512' has value 'BASE64BINARY' which is not an absolute URI.

据我所知，WS2007FederationHttpBinding无法处理这种类型的令牌

我正在寻找如何处理这种情况的解释

客户端代码如下（从IDP获取SAML令牌后）

 var binding = new WS2007FederationHttpBinding();
  binding.Security.Mode = WSFederationHttpSecurityMode.TransportWithMessageCredential;
  binding.Security.Message.IssuedKeyType = SecurityKeyType.BearerKey;
  binding.Security.Message.EstablishSecurityContext = false;
var factory = new WSTrustChannelFactory(binding, new EndpointAddress(SP_EndPoint));
  factory.TrustVersion = TrustVersion.WSTrust13;
  factory.Credentials.SupportInteractive = false;
 var rst = new RequestSecurityToken
  {
    RequestType = RequestTypes.Issue,
    //AppliesTo = new EndpointReference(@"http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous"),
  };

  RequestSecurityTokenResponse rstr;
  var channel = factory.CreateChannelWithIssuedToken(idpToken);
  SecurityToken spToken = channel.Issue(rst, out rstr);
  return spToken;