TypeError: Error #1034: Type Coercion failed: cannot convert flash.events::Event@7fc1

programming flash
1

//variables

var keyLeftPressed:Boolean = false;
var keyRightPressed:Boolean = false;
var keyUpPressed:Boolean = false;
var keyAPressed:Boolean = false;
var keySPressed:Boolean = false;

hero.gotoAndStop(‘idle’);
hero.scaleX=-1;

stage.addEventListener(Event.ENTER_FRAME, enterFrameHandler);
stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDownHandler);
stage.addEventListener(KeyboardEvent.KEY_UP, keyUpHandler);

function enterFrameHandler(e:KeyboardEvent):void
{
if(keyLeftPressed)
{
hero.gotoAndStop(‘walking’);
}
else if(keyRightPressed)
{
hero.gotoAndStop(‘walking’);
}
else
{
hero.gotoAndStop(‘idle’);
}
}

function keyDownHandler(e:KeyboardEvent):void
{
if (e.keyCode == Keyboard.LEFT)
{
hero.gotoAndStop(‘walking’);
hero.scaleX=1;
}
}

function keyUpHandler(e:KeyboardEvent):void
{
if (e.keyCode == Keyboard.LEFT)
{
hero.gotoAndStop(‘idle’);
}

}

i love to know whats wrong with my codes, but i cant see something wrong.
it run, but it has an error on compiler error. im using flash cs5.5 anyway.
tnx in advance, any help will be appreciated. tnx !