window.onload = Init;

function Init()
{
	var allImages;
	var i;
	var max;
	
	allImages = document.getElementsByTagName("img");
	max = allImages.length;

	for (i=0; i < max; i++){
		if (allImages[i].className == "navi_button"){
			allImages[i].onmouseover = changeImage;
			allImages[i].onmouseout = returnImage;
		}
	}
}

function changeImage()
{
	var filePath;

	filePath = this.src.substr(0,this.src.length-5) + "B.gif"
	this.src = filePath;
}

function returnImage()
{
	var filePath;

	filePath = this.src.substr(0,this.src.length-5) + "A.gif";
	this.src = filePath;
}