function subWin(url,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;
	}
	
	if (height) {
		if (window.screen.height > height) 
			features+=", top="+(window.screen.height-height)/2;
		 else 
			height=window.screen.height;
			features+=", height="+height;
	}
	
	winopen=window.open(url,"window",features);
	winopen.focus();
}