I have a similar problem as MNDave. In my case it is a call coming from the auto attendant. I setup the Off-Net forwarding just like it says in the user guide. Program a speed dial bin 9019 then forward the phone to *9019. If a call is answered by another station and is transferred to the x-101..the call forwards Off Net. But If I dial the extension 101 in the auto attendant and it transfers I get a few seconds of silence then the auto attendant greeting restarts.

any ideas about what programming is missing?

Is conferencing enabled for the voice mail ports? Keep in mind that an off-net forward is essentially an unattended conference call. You'll also want to extend the trunk-trunk conference timer out from the default of 10 minutes.

I will have to check both of those things and let you know.

Checked the voicemail ports. This is the Flash Based Voicemail by the way. Anyway I checked the following on all the voicemail extensions.
Conference = Enabled
System Speed Dial = Enabled
Call Forward = Enabled
Line Group Access = group 1 enabled.
All the settings were enabled already. I didn't change anything.
conference/disa timer I changed from 10 to 60.
When the call is transferred by the Auto Attendant to the extension I was watching to see if one of the trunk buttons lights, other than the one I was on. It doesn't.

There is a software bug in the voice mail, you need to have extension 101 no answered forwarded to a station that is off net forwarded, so 101 would be forwarded to another station, say 201 and 201 is forwarded off net. Sounds convoluted but it should work.

The Flash VM has limitations but if the system is an XTSc (or STS) it is really easy if you use one of the included SLT ports and forward it. This works quite well.