OpenSAML user discussion

Hi,

I'm trying to use opensaml-2.1 too, and I'm having some troubles using the 
binding.
I need to send an AttributeQuery to a servlet from an Identity 
Provider(another servlet) or from an application. In opensaml-1.1 I only had 
to do something like:

  SAMLBinding binding = SAMLBindingFactory.getInstance(SAMLSOAPBinding.SOAP);
  SAMLResponse response = 
binding.send("http://www.example.com/AttributeServlet/",samlRequest);

but in opensaml-2.1 I need to use a HttpServletRequestAdapter, whose need a 
javax.servlet.http.HttpServletResponse, and I don't no how can I create a 
HttpServletResponse.
I have seen the examples tests, and I have seen that it use a 
MockHttpServletResponse to create the HttpServletResponse, but this class is 
only used for testing and not send anything to the Attribute Servlet.
How can I send a Query using the opensaml-2.1 bindings?

Thanks.
Gines.