window.onload = onclickInit;

function onclickInit() {
	for (var i=0; i<document.images.length; i++) {
		if (document.images[i].className.search("port_nav_img") != '-1') {
			setupOnclick(document.images[i]);
		}
	}
}

function setupOnclick(thisImage) {
	thisImage.clickImage = new Image();
	thisImage.clickImage.src = "http://www.miaangelica.com/" + thisImage.id ;
	thisImage.onclick  = clickOn;
}

function clickOn() {
	document.getElementById('main_portfolio_image').src = this.clickImage.src;
}