PEAR SOAP package - WS-Security

Posted on the general list last week but got no response so am trying here... Hello, can anyone tell me if the SOAP package supports WS-Security for SOAP messages? I have looked a little at the SOAP package pages and source repository but do not see anything dealing with configuring or consuming the Soap Security header. For more background, and possibly a better answer to my overall objective, I am interested in writing a Drupal module to be a Soap client of a secure web service running on a j2ee platform. The service is protected using WS-Security 1.1 protocols for mutual certificate tokens. So far I've not found a module dealing with this directly so I think I may need to write my own - that should be a fun first PHP project (LoL!) - does the Soap package have any support for writing the Security headers? Thanks for entertaining my ignorance, Andrew