I meant extensions_custom.conf not extensions_additional.conf as they would get overwritten.
The Voipinfo page below had a log of good information:
http://www.voip-info.org/wiki/view/Asterisk+Cisco+CallManager+Voicemail+Integration
This is the script that I am using (mostly from the link above) to turn mwi on and off. Just add the script location to externnotify and MWI should work.
#!/bin/bash
CONTEXT=$1
EXTEN=$2
NUMVMS=$3
Turnoff=“Channel: SIP/1002@callman\nCallerid: $EXTEN\nMaxRetries: 0\nRetryTime: 5\nWaitTime: 5\nContext: $CONTEXT\nExtension: $EXTEN”
Turnon=“Channel: SIP/1003@callman\nCallerid: $EXTEN\nMaxRetries: 0\nRetryTime: 5\nWaitTime: 5\nContext: $CONTEXT\nExtension: $EXTEN”
if [[ $NUMVMS = “0” ]]; then
echo -e $Turnoff >> /var/spool/asterisk/outgoing/$date.call
else
echo -e $Turnon >> /var/spool/asterisk/outgoing/$date.call
fi
The next step for me is to try to integrate the IMAP setting to work with Exchange 2010. I am not sure if this is possible or not but I am going to try.