function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}
function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}
var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		m_musiba_over = newImage("images/m_musiba-over.png");
		m_sisyu_over = newImage("images/m_sisyu-over.png");
		m_yobou_over = newImage("images/m_yobou-over.png");
		m_kyousei_over = newImage("images/m_kyousei-over.png");
		m_inp_over = newImage("images/m_inp-over.png");
		m_sinbi_over = newImage("images/m_sinbi-over.png");
		m_gaku_over = newImage("images/m_gaku-over.png");
		m_basyo_over = newImage("images/m_basyo-over.png");
		m_innai_over = newImage("images/m_innai-over.png");
		m_staff_over = newImage("images/m_staff-over.png");
		m_tiryou_over = newImage("images/m_tiryou-over.png");
		m_tousyo_over = newImage("images/m_tousyo-over.png");
		m_osirase_over = newImage("images/m_osirase-over.png");
		m_link_over = newImage("images/m_link-over.png");
		m_blog_over = newImage("images/m_blog-over.png");
		m_index_over = newImage("images/m_index-over.png");
		preloadFlag = true;
	}
}