UI.List simple question

I have a list object such as this:

var a =['a','b','c']

listObj = new AW.UI.List;
listObj.setId("myList");

for (i=0;i<a.length;i++) {listObj.setItemText(a[i],i)}
listObj.setItemCount(a.length);

What can I add so that a function is called when the user presses
the Enter key? listObj.onKeypressed . . . ?

listObj.onKeyEnter = function(event){...}

http://www.activewidgets.com/aw.system.control/control-keyboard-events.html