Preloader script returns error

[andorosfire]

I followed a video tutorial to the letter and watched as his code worked and mine returns errors. They are identical and yet.......FAIL. Here is the code. Can some one help me?

stop();

var percentage:Number;

onEnterFrame = function()
{
    if(getBytesLoaded() >= getBytesTotal())
    {
        gotoAndStop(2);
        delete onEnterFrame;
    }
    
    percentage = Math.round((getBytesLoaded() / getBytesTotal() )*100);
    bar._xscale = percentage;
    //trace(percentage);
}

here is the link to the video if it helps you help me.
http://www.viddler.com/explore/dorklessons/videos/12/

And here are the errors that I receive.
**Error** Scene 1, Layer 'actions', Frame 1, Line 5: 1120: Access of undefined property onEnterFrame.
onEnterFrame = function()

**Error** Scene 1, Layer 'actions', Frame 1, Line 7: 1180: Call to a possibly undefined method getBytesLoaded.
if(getBytesLoaded() >= getBytesTotal())

**Error** Scene 1, Layer 'actions', Frame 1, Line 7: 1180: Call to a possibly undefined method getBytesTotal.
if(getBytesLoaded() >= getBytesTotal())

**Error** Scene 1, Layer 'actions', Frame 1, Line 10: 1120: Access of undefined property onEnterFrame.
delete onEnterFrame;

**Error** Scene 1, Layer 'actions', Frame 1, Line 13: 1180: Call to a possibly undefined method getBytesLoaded.
percentage = Math.round((getBytesLoaded() / getBytesTotal() )*100);

**Error** Scene 1, Layer 'actions', Frame 1, Line 13: 1180: Call to a possibly undefined method getBytesTotal.
percentage = Math.round((getBytesLoaded() / getBytesTotal() )*100);

Total ActionScript Errors: 6, Reported Errors: 6

[andorosfire]

I just realized this is AS2 code. Why would someone teaching a CS3 course use AS2? Does anyone know how to write the AS3 version of this code?
Thanks