A method of operating a multifunction device includes displaying a soft keyboard having a plurality of unconditionally enabled buttons and one or more conditionally enabled buttons, detecting a first input with a first button at a first time, and responding to detecting the first input by activating the first button. In response to detecting a second input with a second button at a second time, when the first button is an unconditionally enabled button and the second button is an unconditionally enabled button, the second button is activated. When the second button is a conditionally enabled button, and when the period of time between the first and second times is above a predefined threshold, the second button is activated; and when the period of time between the first and second times is equal to or below the predefined threshold, the second button is prevented from being activated.