XML version of a Rails-generated list function

For the purpose of calling from a Flex HTTPService, I need to create
an XML version of the Rails-generated list() function. The original
is:

def list
@rv_wrk_medical_staff_pages, @rv_wrk_medical_staffs =
paginate :rv_wrk_medical_staffs, :per_page => 10
end

I tried applying to_xml() to @rv_wrk_medical_staffs, but get the
following error message:

“Not all elements respond to to_xml”

Thanks,

Chris.