What worries me is that the HTTP::Headers change happened in 2011 which is why I need a sanity check as to whether SOAP::Lite is truly broken in the webservice mode.

Maybe you need to load Apache2::compat

Maybe Apache2::SOAP might help

:) I've looked inside SOAP::Lite more than once, but I can't reason about it from memory, or give you an answer to your question -- I doubt even the developer of SOAP::Lite could do that

There is a server/client example somewhere in my treasure trove of soap examples and lost knowledge update: its at Re: SOAP::Lite server - changing method name in response

Adapt it, use it to demonstrate a problem or ease your fears