JavaScript: Object expected

[Metaphor]

A common error, since it's so damned general that noone understands what it's pointing at. ;)

Well. I've got myself a function in an external .js file.

function swapImage(imgID, imgFile) {
	document.images[imgID].src = '/newdesign/images/menubuttons/' + imgFile;
}

Simple as can be, right? Right.

Then, naturally, I've got an onMouseOver on a link that goes:

<a href="" onMouseOver="swapImage('imgHome','home_down.gif')"><img name="imgHome" src="home.gif"></a>

I can't for the life of me see anything wrong. Am I stupid? Is javascript stupid? Is the answer to the question about life, the universe and everything not 42?

[Metaphor]

Never mind. ^^

I was making an error in a completely different location that mungled the relative paths to the external .js. How stupid of me.

[rpungin]

In general, use Mozilla/Netscape javascript console to get more meaningful error messages. Just type javascript: in the address bar.

[Metaphor]

It wasn't even a javascript error, so I doubt that would help. But thanks.