I'm trying to send the key press 0# to an old SIP intercom system to open a gate.
This works from the SIP phones but not from the touchpanels.

Is this supported on TSW's?

It's most likely an in-band/out-of-band issue.
You can send SIPAUDIOMODE to see what mode it is in.
SIPAUDIOMODE RFC2833 ON and SIPRESTART will set it to out-of-band.
SIPAUDIOMODE RFC2833 OFF and SIPRESTART Will set it to in-band mode.

Awesome, Thanks Eric that worked.
Regards
s