[Asterisk-Users] Can the originator of a call transfer it?

[Steve Prior]

I've been getting familiar with call parking between a SIP extension
and a Zap extension.  I noticed that if either extension calls the 
other, then on the receiving phone I can press #70 to transfer the call
to the parking extension.  However, the phone that originated the call
cannot do so.  This is important to me because in a home setting I
want to be able to make a call from one phone and then switch to
using a different one to continue the call.

Am I missing some bit of configuration that would allow this?

Thanks
Steve