function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}
function changeImagesArray(array) {
	if (preloadFlag == true) {
		var d = document; var img;
		for (var i=0; i<array.length; i+=2) {
			img = null; var n = array[i];
			if (d.images) {img = d.images[n];}
			if (!img && d.getElementById) {img = d.getElementById(n);}
			if (img) {img.src = array[i+1];}
		}
	}
}

function changeImages() {
changeImagesArray(changeImages.arguments);
}


var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		pre_globalbnavi_01 = newImage('./images/globalbnavi_01.gif');
		pre_globalbnavi_02 = newImage('./images/globalbnavi_02.gif');
		pre_globalbnavi_03 = newImage('./images/globalbnavi_03.gif');
		pre_globalbnavi_04 = newImage('./images/globalbnavi_04.gif');
		pre_globalbnavi_06 = newImage('./images/globalbnavi_06.gif');
		pre_mail_bottan_on = newImage('./images/mail_bottan_on.gif');
		pre_co1_on = newImage('./images/co1_on.gif');
		pre_co3_on = newImage('./images/co3_on.gif');
		pre_co4_on = newImage('./images/co4_on.gif');
		pre_co2_on = newImage('./images/co2_on.gif');
		
		preloadFlag = true;
	}
}