XI and Soap with attachments

We have a Http -> XI(3.0)-> Webservice scenario, where the webservice returns a SOAP response with one or more zip file as attachments.

Any information on configuring SOAP adapter to receive the multiple attachments and pass it to outbound http interface will be helpful.

Inorder to test this scenario, we are also looking for a webservice which can return one or more attachments. Please let us know if you happen to know of a similar webservice.