The rayo plugin uses the SIP plugin for openfire to link the xmpp user to a SIP profile and registration with a SIP proxy. If you want to call SIP addresses directly instead of phone numbers, you don’t need the openfire SIP plugin. To make it work, you need to develop your own web client using the strophe and the rayo strophe plugin provided. In the source, there is a demo folder with a working demo web client. Copy it to OPENFIRE_HOME/resources/spank and go to https://your_server:7443/demo or whatever name you gave to the demo folder.