I've ran into services in the past that supported WS-Addressing, but it was only recently that I worked with one requiring it in addition to WS-Security. It's not very difficult to implement, but I threw together a library for anyone else that might need to leverage it.
WS-Addressing Library: soap-wsa.php
WS-Addressing Example: soap-wsa-example.php
The example also uses WS-Security (not required for WS-Addressing) but demonstrates some new WS-Security functionality.