Giuseppe, unfortunately not. By the time the message reaches your endpoint Axis has already parsed the message and recorded the SAX events.
Also, the SAAJ view of the message is W3C DOM based, so the incomming message is already an in memory DOM tree.
Your best bet might be, to forget about Axis and route you WS requests to a plain web application (I assume you use HTTP transport). This is especially true is you are not using JAXRPC handlers and such.
Lazy loading of the request message is a requirement of our new JBossWS implementation.