Concretando el rollito de antes...a ver si esto te soluciona algo:
Options during a call
Many of the options that you can use during a call are network services. For availability, contact your network operator or service provider.
Press Options during a call for some of the following options:
Mute or Unmute, Contacts, Menu, Record, Lock keypad, Auto volume on or Auto volume off, Loudspeaker or Handset, and the network services Answer and Reject, Hold or Unhold, New call, Send DTMF (to send tone strings), Swap (to switch between the active call and the call on hold), Transfer (to connect a call on hold to an active call and disconnect yourself), Conference (to set up a conference call), Private call (to discuss privately in a conference call), End call, and End all calls.
Claro que todo eso viene en el manual del movil...jijijijiji,