How to build a static library with third party framework in Objective-C

Question

I am trying to build a static library which is using a third party framework in Objective-C. I created static libs following this article http://www.icodeblog.com/2011/04/07/creating-static-libraries-for-ios/

It is built successfully. But, when i am binding this static library into my xamarin.ios application, Xamarin studio display: "Wrapper type 'Soft.Payleven.SPayleven' is missing its native ObjectiveC class 'SPayleven’.”

My ApiDefinition.cs (At the moment I only would like to create object)

namespace Soft.Payleven
{   
    [Protocol]
    [BaseType (typeof (NSObject))]
    interface SPayleven 
    {
    }
}

Xcode Version 6.4

Xamarin Studio 5.9.5

Thanks in advance.