window.onload = function () {
	//Pre-load images
	if (document.images) {
		loadovers = [];
		for (var i=0; i<3; i++) {
			loadovers[i] = new Image();
			loadovers[i].src = 'images/subbtn_sel0' + (i+1) + '.gif';
		}
	}

	//Buttons
	var subnav01 = document.getElementById('subnav01');
	var subnav02 = document.getElementById('subnav02');
	var subnav03 = document.getElementById('subnav03');
	if (subnav01 && subnav01.src.indexOf('images/subbtn_sel01.gif') == -1) {
		subnav01.onmouseover = function () { subnav01.src = 'images/subbtn_sel01.gif'; };
		subnav01.onmouseout = function () { subnav01.src = 'images/subbtn_01.gif'; };
	}
	if (subnav02 && subnav02.src.indexOf('images/subbtn_sel02.gif') == -1) {
		subnav02.onmouseover = function () { subnav02.src = 'images/subbtn_sel02.gif'; };
		subnav02.onmouseout = function () { subnav02.src = 'images/subbtn_02.gif'; };
	}
	if (subnav03 && subnav03.src.indexOf('images/subbtn_sel03.gif') == -1) {
		subnav03.onmouseover = function () { subnav03.src = 'images/subbtn_sel03.gif'; };
		subnav03.onmouseout = function () { subnav03.src = 'images/subbtn_03.gif'; };
	}
};