RadTreView for ASP.NET load on demand AJAX is not connecting correctly
===

I am working on a project and i get the following casting errror:

    Unable to cast object of type 'System.Object[]' to type
    'System.Collections.Generic.IDictionary`2[System.String,System.Object]'.

From the Telerik website, I was following the example: http://www.telerik.com/help/aspnet-ajax/treeview-load-on-demand-webservice.html

My program crashed at the server side code, when trying to cast the context and put it into the contextDictionary:

    public RadTreeNodeData[] getNodesWEBSERVICE(RadTreeNodeData node, object context)
        {
            IDictionary<string, object> contextDictionary = (IDictionary<string, object>)context;
            ....
        }

The only difference from what i am thinking is the definition.  I am using RESTful services, instead of [WebMethod].  THat means instead of the [WebMethod] above the method, i have a page for:

    [OperationContract]
        [WebInvoke(Method = "POST",
            ResponseFormat = WebMessageFormat.Json,
            BodyStyle = WebMessageBodyStyle.Wrapped,
            UriTemplate = "getNodesWebservice")]
        RadTreeNodeData[] getNodesWEBSERVICE(RadTreeNodeData node, object context);

Everything fires correctly and gets into the method, but the information is not casted.  I was trying to figure out why.  Since the RESTful was is doing an ajax call, i was thinking that the methods needed to be strings which would be populated with the json data and parsed accordingly.

If you need additional information, i will post it.