it would really help to see what you're trying to end up with after serialization.

If you don't give us more info, we can't help. The XML string that you are trying to pass would be very useful so we know exactly what you are trying to create. At the very least, the WSDL that you're trying to validate against.

As you said you know WSDL, you would know that there are plenty of ways to represent the same data. SOAP::Lite by default uses RPC/encoded, which may have unwanted information if you're trying to do document/literal, especially if the other end can't properly deserialize references.