Discussion: Asterisk Disconnect Supervision

Just a quick thank note to JazEzork for solving a month old problem.
FXO lines were held up after remote caller hangup for as long as 4 minutes (IVR message + voicemail timeout).
I am using Trixbox 1.1 and Digium TDM400P card with 4 FXO channels.
After checking all suggestions I added following two lines to zapata.conf:
callprogress=yes
busydetect=yes

I am using FreePBX linked to a Nortel Meridian 1 Option 11c via a TDM400P and 4 analogue lines to the Meridian. I think I have enabled everything I can on the Meridian for disconnect supervision via the OTM control software, but I am not a Meridian Expert. If I call one of the VOIP phones connected to Asterisk direct from the meridian and then hang up before asterisk voice mail has chance to kick in the call is disconnected as expected after a few seconds. If I answer the phone then disconnect at the Meridian end, I hear a continues tone as expected.

The problem starts when the call progresses to a queue, a voice menu or voice mail. Once at that stage, hanging up at the meridian end has no effect on the call and it progresses through the system. When checking the Asterisk CLI, you can see that music and messages are still being played as the though the call was still connected.

Does anyone have ideas how I can overcome this problem?

Thanks