Guessing you're in Austalia ?
With the North American phones you need a headset amplifier and top to make it work.
You connect it to where the handset normally connects and the handset plugs into the amplifier.It is also handy to have a headset key although you can turn the feature on/off with a code.That info should be in your user guide.

[This message has been edited by pvj (edited October 25, 2004).]