if (document.images) {

	tabhomeon = new Image
	tabhome = new Image
	tabhomeon.src = "/images/tabhome_on.gif"
	tabhome.src = "/images/tabhome.gif"

	tabgalleryon = new Image
	tabgallery = new Image
	tabgalleryon.src = "/images/tabgallery_on.gif"
	tabgallery.src = "/images/tabgallery.gif"

	tabmapon = new Image
	tabmap = new Image
	tabmapon.src = "/images/tabmap_on.gif"
	tabmap.src = "/images/tabmap.gif"

	tabclasseson = new Image
	tabclasses = new Image
	tabclasseson.src = "/images/tabclasses_on.gif"
	tabclasses.src = "/images/tabclasses.gif"

	tabnihongoon = new Image
	tabnihongo = new Image
	tabnihongoon.src = "/images/tabnihongo_on.gif"
	tabnihongo.src = "/images/tabnihongo.gif"

	tabenglishon = new Image
	tabenglish = new Image
	tabenglishon.src = "/images/tabenglish_on.gif"
	tabenglish.src = "/images/tabenglish.gif"
	
}
else {

	tabhomeon = ""
	tabhome = ""
	document.tabhome = ""

	tabgalleryon = ""
	tabgallery = ""
	document.tabgallery = ""

	tabclasseson = ""
	tabclasses = ""
	document.tabclasses = ""

	tabmapon = ""
	tabmap = ""
	document.tabmap = ""

	tabnihongoon = ""
	tabnihongo = ""
	document.tabnihongo = ""

	tabenglishon = ""
	tabenglish = ""
	document.tabenglish = ""

}

function imggifOn(thisImg) {
	document[thisImg].src = "/images/" + thisImg + "_on.gif"
}

function imggifOff(thisImg) {
	document[thisImg].src = "/images/" + thisImg + ".gif"
}

function imgjpgOn(thisImg) {
	document[thisImg].src = "/images/" + thisImg + "_on.jpg"
}

function imgjpgOff(thisImg) {
	document[thisImg].src = "/images/" + thisImg + ".jpg"
}