(function(){

var replacePNG = function() {
	var imgs = document.body.getElementsByTagName("img");
	var theSorce;
	for (i = 0; i < imgs.length; i++) {
		theSorce = imgs[i].src; 
		if (theSorce.indexOf(".png") != -1) {	//画像がpng形式なら
			imgs[i].src = "images/blank.gif";
			imgs[i].style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + theSorce + "',sizingMethod=image)";
		}
	}
}

if (typeof(document.documentElement.style.maxHeight) == "undefined") {	//IE6以下なら
	if (window.attachEvent) {
		window.attachEvent("onload", replacePNG);
	}
}

})()