How to call wcf function from as3

Question

I have been cosuming webservices using alducente.services.WSDL classes with old ASP.NET services from Flash.

Trying the same as3 calls with the new WCF services I get the error that the method I am calling does not exist.

According to http://stackoverflow.com/questions/1614157/flash-connecting-to-a-wcf-service I have declared the function on IService as follows

<OperationContract()> _
    <WebInvoke(UriTemplate:="Sub?x={x}&y={y}", BodyStyle:=WebMessageBodyStyle.Bare, RequestFormat:=WebMessageFormat.Xml, ResponseFormat:=WebMessageFormat.Xml)> _
    Function Subtract(ByVal x As Long, ByVal y As Long) As Long

but that fixed nothing. Also I tried putting on web.config the tag but is not recognized.