asterisk users - Jul 2003 - Call Transfer Anouncement

Ok the scenario  want to acheive is:

Call between A and B is established.  A wants to transfer B to C, so A presses 
# and then the extension of C.  This puts B on hold, and a connection between A 
and C is established.  Then, when A hangs up the call, B and C get connected.

I am using H323 phones, at the moment when A dials # and the extension of C, A 
is immediately cut off, and the B gets connected to C..

Any ideas?