[Serusers] Re: How Do I Enable Session Timers On PSTN->SIP Calls?

Hi All. Our PSTN gateway supports Session-Expires for re-INVITEs. The session timer is "automagically" enabled when dialing SIP->PSTN. However, when calling PSTN->SIP re-INVITEs do not happen, however the PSTN GW does support them. I think the problem is that PSTN->SIP calls need to (for some reason) explicitly request session timers. How would I request this? I know I can add the "Session-Expires: 120;refresher=??" header, but do I then do this in the 200OK response back to the PSTN GW? Also, if the PSTN->SIP call is asking the PSTN GW to enable session timers, would the "refresher=" tag be set to UAS or UAC? Regards, Paul