function donothing(){}
function display_prodopt(foo,ref) {
	foo = foo.value;
	
	if (foo != '') 
	{
		foo = foo.replace(/ /g, "_");
		foo = foo.replace(/\//g, "_");
		foo = foo.replace(/-/g, "_");
		foo = foo.replace(/\%/g, "_");
		doc = "document.";
		prod = "product.";
		val = ".value";
		new_image = eval(doc + prod + foo + ref + val);
		blank_image = eval(doc + 'blank' + ref);
	
		if (new_image == 'none')
		{
			blank_image.src = '../images/product_option/blank_option.jpg';
		}
		else
		{
			blank_image.src = '../images/product_option/' + new_image;
		}
	}
	else
	{
		blank_image.src = '../images/product_option/blank_option.jpg';
	}
}