how to access wcf service in IOS Platform using Xamarin

I am Creating xamarin IOS Application.I want to consume wcf service.I have gone through this link. and generate proxy from window and include it on xamarin ios project on MAC. My Issue is when i am calling its method like as login Like following code-

 MobileClient client=new MobileClient(binding,new EndPointAddress("http://pilat.brisbanepilots.com.au:6969/Service.svc"))

client.Login("username","pass","deviceTokenId");

But It Returning the Following Issue-

System.InvalidOperationException:
MonoTouch does not support dynamic proxy code generation.Override 
this menthod or its caller to return specific client proxy instance

I am pulling my hair from 2 days in this Issue.Please help me. Any help will be highly Appreciated.