simple AS3 converter not working :(

Hi guys

I am really stuck with this assignment i am supposed to hand in tomarrow ! so would appreciate any help.

I have been told to make a simple converter using as3 in flash to convert kilometers to miles, even though I am kinda sure my code is correct, when i test the movie, type a random number and press enter, nothing happens :(

here is the code:
kilometers_txt.addEventListener(KeyboardEvent.KEY_ DOWN,convertKilometers);
function convertKilometers(k:KeyboardEvent)void:{
var kilometers:Number;
var miles:Number;
{
if (k.keyCode==Keyboard.ENTER) {
kilometers=Number(km_txt.text);
miles=kilometers / 1.61;
miles_txt.text=String(miles);


}
}
I really reallly would appreciate any help. p.s i can even send u the .flv file :(
thank you :)

please don't double post :)