function createNavEvent (count) {
	for (var i=0;i<count;i++){
		var nav = document.getElementById ('nav'+(i+1));
		
		if (nav){

		nav.normalImg = nav.src;
		nav.onmouseover = function () {
			this.src = this.src.replace (/_normal\.gif/gi, '_over.gif');
		}
		nav.onmouseout = function () {
			this.src = this.normalImg;
		}
		}
	}
	
}
function init () {
	window.createNavEvent (8);
}
init ();