exposing WCF via GET method

hi all

i have been struggling with this for a while. i have followed lots of tuturials and basically they are always the same , but mine just doesnt work.

Interface :

    [ServiceContract]
    public interface IRestServiceImpl
    {
        [OperationContract]
        [WebInvoke(Method = "GET",
                    ResponseFormat = WebMessageFormat.Xml,
                    BodyStyle = WebMessageBodyStyle.Wrapped,
                    UriTemplate = "XML")]
        String  DoWorkXML();

        [OperationContract]
        [WebInvoke(Method = "GET",
                    ResponseFormat = WebMessageFormat.Json,
                    BodyStyle = WebMessageBodyStyle.Wrapped,
                    UriTemplate = "JSON")]
        String DoWorkJSON();
    }

Implementation :

    public class RestServiceImpl : IRestServiceImpl
    {
        public String DoWorkXML()
        {
            return "Dados XML";
        }

        public String DoWorkJSON()
        {
            return "Dados JSON";
        }
    }

my webconfig :

<?xml version="1.0"?>
<configuration>

  <system.web>
    <compilation debug="true" targetFramework="4.0" />
  </system.web>
  
  <system.serviceModel>

    <services>
      <service name="RestService.ResServiceImpl" behaviorConfiguration="ServiceBehaviour">
        <endpoint address="" binding="webHttpBinding" contract="RestService.IRestServiceImpl"
                  behaviorConfiguration="web">
          
          
        </endpoint>
      </service>
    </services>
    
    <behaviors>
      <serviceBehaviors>
        <behavior name="ServiceBehaviour">
          <serviceMetadata httpGetEnabled="true"/>
          <serviceDebug includeExceptionDetailInFaults="false"/>
        </behavior>
      </serviceBehaviors>

      <endpointBehaviors>
        <behavior name="web">
          <webHttp/>
        </behavior>
        
      </endpointBehaviors>
    </behaviors>
    
    <serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
    
  </system.serviceModel>
  
 <system.webServer>
    <modules runAllManagedModulesForAllRequests="true"/>
  </system.webServer>
  
</configuration>

1 . as soon as i do the third step (webconfig file) the vs2010 automatic client (the little application vs2010 creates) stops working (gives some error).  

2 - when i go to http://localhost:43658/RestServiceImpl.svc on my browser , i dont have the wsdl option. actualy it states that "Metadata publishing for this service is currently disabled. "

(if i revert webconfig back to the original  1 and 2 works ok)

3 - all the tuturials i followed are to use GET method, so they all say .....goto http://localhost:43658/RestServiceImpl.svc/XML and http://localhost:43658/RestServiceImpl.svc/JSON , but when i try this ( with original webconfig or changed with third step it doesnt matter ) it always returns page not found.

what am i doing wrong ?

thks in advanced

rui