function m_win(url,windowname,width,height) {
	var features="location=no, menubar=no, status=yes, scrollbars=yes, resizable=yes, toolbar=no";
	if (width) {
		if (window.screen.width > width)
			features+=", left="+(window.screen.width-width)/2;
		else width=window.screen.width;
			features+=", width="+width;
	}
	window.open(url,windowname,features);
}