SOAP::Lite with large web service payloads

We're currently interoping with .Net applications via web services to
consume large amounts of data (70 MB +-). The service response
payloads have been streamlined to return single string values that
contain pipe delimited data. We've found that the processing of the
SOAP message seems to blow-up the memory footprint to at least 7x the
payload! I'm assuming that this occurs because the SOAP message is
loaded in to an XML DOM or something. Does anyone know of an
alternative module that we can use to consume large web service
payloads? Is there one that streams the SOAP message out without
wrapping it up first?

Thanks in advance!