Is there any rfc on this or is it something that snom just made up? On Nov 23, 2009, at 3:00 AM, Keith Laaks wrote:

Hi,

I have tried maintaining charging information on a SNOM 300's display using 'display' - but found that the phone has some timer, whereby every 60 seconds it wipes out whatever happens to be on the display at that time and replaces is with the dialled number. So not a viable option as it impacts usability. Really annoying when the display was just updated with valuable information for the user and a split second later it gets replaced. [If somebody knows how to disable this behaviour - please do tell...]

I see that SNOM supports a number of features for Advice of Charge.

...

From their Wiki:

http://wiki.snom.com/Advice_of_charge_%28AOC%29_in_SIP Example of an SIP-Info Message:

----------------------------------------------------- INFO sip:bla@snom.com SIP/2.0 From: <biller@snom.com>;tag=5354n3 To: <ua@snom.com>;tag=33rfh3 CSeq: 23423 INFO Call-ID: 3452tw43dt354dm03 AOC: charging;state=active; charging-info=currency; currency=EUR; amount=2000; multiplier=0.001 Content-Length: 0 -----------------------------------------------------

So the question - Is there some method available today to add these additional 'new' headers to an INFO message I can send out to these phones?

If not, I guess it's a matter of looking at enhancing the "case SWITCH_MESSAGE_INDICATE_DISPLAY" section in mod_sofia.c ?