Extension Method dll

I 'have created an Extension method in dll plugin like this.

public static class MonoBehaviourExt  {
    public static ExtendedWWW WWWRequest(this MonoBehaviour ext,ExtendedWWW myCoroutine){ 
  ......
    }
}

but , in unity i get this error :
Unhandled Exception: System.Reflection.ReflectionTypeLoadException: The classes in the module cannot be loaded.

I think that is related to Extension Method declaration, in fact if I replace “this MonoBehaviour ext,” with “MonoBehaviour ext”, compiler works fine.

Any idea?
Thanks

You wrote the same thing twice. What are you replacing it with ?

Sorry, I’ have corrected …