Need assistance in putting a cordless Toshiba handset on a 424i. I am using it in conjunction with an existing station, which has call appearances for 2 other extensions. I want the person to be able to get calls for either the base extensions or either of the 2 secondaries. The 4 function buttons emulate the first four places in the phone setup. Can I make it so they can place a call on hold and answer the second call? Thanks