[OpenSER-Users] XMPP Gateway

Dear All I am trying to achieve a setup where users can both chat using XMPP and do voice calls through VOIP. I have already setup eJabberD and I like it's features and I am almost done setting up OpenSer. I have read about the XMPP Gateway module ? If I do use this plugin will this synchronize the users created between the two systems if I do create them on the OpenSer server ? Has anyone used the module ? If I do use it will the contact lists for the users be stored on the SIP server or the XMPP server ? What about presence will the XMPP be responsible for the presence changes or the OpenSer server ? Thanks