I've been dealing with SOAP for a while already and I must say that the module you should use is XML::Compile::SOAP. Or, if possible, SOAP::Simple (which is just an abstraction for it). If you want to make a web app with support for web services, I'd recommend using Catalyst with Catalyst::Controller::SOAP. (If you're in Catalyst, you can also use Catalyst::Model::SOAP to consume web services).
SOAP::Lite is relevant in archeological terms, but it doesn't implement SOAP as it has been used in the last decade.