Namespace Prefix in Response Element child nodes

[MowTin]

In my .Net web service. I want to declare all the namespaces in my soap response element and have all the child elements use prefixes. I know how to use XmlNamespaceDeclarations but I don't know how to apply them to the response element.

I have: <soap:body>
<MyMethodResponse >
<MyElement xmlns="blah1">
<MyElement2 xmlns="blah2">
....

I want: <soap:body>
<MyMethodResponse xmlns:b1="blah1" xmlns:b2="blah2">
<b1:MyElement>
<b2:MyElement>
...

How do I do it?