[SR-Users] how to configure presence module with websocket

hello. I am tring to SUBSCRIBE for presence status of a user on my kamailio server using the sipMl5 (over websockets) but kamailio failes. (more exactly the handle_subscribe failes.) I was told previusly by peter dunkly that it is not a bug, just a configuration problem. I am quoting his answer: "This is a configuration problem not a bug in the software. SUBSCRIBEs are dialog forming requests and NOTIFYs (in this scenario) are in-dialog requests. As such you need to use force_rport(), add_contact_alias(), and handle_ruri_alias() with presence dialogs in the same way you do with media session dialogs." How can i acheve this ? thanks in advance...