public int getServerSessionTimeout() {
        return JiveGlobals.getIntProperty("xmpp.server.session.timeout", 5 * 60 * 1000);
    }
Returns the number of milliseconds to elapse between clearing of idle server sessions.

@return the number of milliseconds to elapse between clearing of idle server sessions.
xmppserver/src/main/java/org/jivesoftware/openfire/SessionManager.java