Transfer an outbound call while it is ringing

Should it be possible to transfer an outbound call before it is answered by the receiving end? I have tried to do this but the call does not transfer. I have checked to see that call transfer is working, and it does once the outbound call has been answered.

The situation is one where I need to block a particular extension from making outbound calls, but allow someone else to initiate an outbound call from another extension and then transfer it to the blocked extension while it is still ringing (before the number being called answers).

I have been able to block outbound calls by changing that extension’s context to “ext-local”, but I cannot seem to transfer a call till it is answered by the receiving end.

Anyone have any ideas on how to accomplish this?