d = document;
p = 'images/nav_';
f = '.gif';
n = '_on.gif';

if (d.images) {
	var u1 = new Image(); u1.src = p+'1'+f;
	var u1Ovr = new Image(); u1Ovr.src = p+'1'+n;

	var u2 = new Image(); u2.src = p+'2'+f;
	var u2Ovr = new Image(); u2Ovr.src = p+'2'+n;

	var u3 = new Image(); u3.src = p+'3'+f;
	var u3Ovr = new Image(); u3Ovr.src = p+'3'+n;

	var u4 = new Image(); u4.src = p+'4'+f;
	var u4Ovr = new Image(); u4Ovr.src = p+'4'+n;

	var u5 = new Image(); u5.src = p+'5'+f;
	var u5Ovr = new Image(); u5Ovr.src = p+'5'+n;

	var u6 = new Image(); u6.src = p+'6'+f;
	var u6Ovr = new Image(); u6Ovr.src = p+'6'+n;
}