Does anyone know how I can send from ser a NOTIFY (or is perhaps INFO) message to a Cisco ATA 186 or other UA to turn on/off the message waiting indicator for voicemail. The Cisco ATA is capable of playing a stuttered dial tone to indicate voicemail but I cannot find any documentation on how to toggle this tone on/off from the proxy. I also have other sip phones like the Grandstream where I would like to signal the MWI to it as well. Does anyone know how this can be done? I assume via the ser_fifo, but what kind of message and what should it look like?

-- Josh