var img1 = new Image(); img1.src = '../graphics/btn_philosophy_on.gif';
var img2 = new Image(); img2.src = '../graphics/btn_smartmarketing_on.gif';
var img3 = new Image(); img3.src = '../graphics/btn_implementation_on.gif';

function setEvents(){
	var ids = new Array("philosophy","smartmarketing","implementation");
	for(var i=0; i<ids.length; i++){
		var id = ids[i]; // get id from array
		var obj = document.getElementById(id); // get doc obj
		if(typeof obj.parentNode.href != "undefined"){
			/* assign events */
			obj.onmouseover = function(){this.src = '../graphics/btn_' + this.id + '_on.gif';}
			obj.onmouseout = function(){this.src = '../graphics/btn_' + this.id + '.gif';}
		}
	}
}
window.onload = setEvents;