Sending DTMF to another channel on hang up

I have a meetme conference setup.
When one of the participants hangs up I want to be able send a DTMF sequence to the other members of the conference.
I know the channel identifiers of the participant members, I don’t know how to send DTMF to a different channel to the current channel context.

Any ideas?

ConfBridge in Asterisk 10 allows DTMF passthrough: … fBridge+10