function openWindow(url, width, height, sizeable)
	{
		if (sizeable==null) sizeable=true;
		if (sizeable) sizeable = ',resizable,scrollbars'
		else sizeable = '';
		if (!width) width=screen.availWidth*.8;
		if (!height) height=screen.availHeight*.8;
		var openWin = window.open(url,'_blank','width=' + width + ',height=' + height + ',screenX=' + ((screen.availWidth-width)/2) + ',left=' + ((screen.availWidth-width)/2) + ',screenY=' + ((screen.availHeight-height)/2) + ',top=' + ((screen.availHeight-height)/2) + sizeable);
		openWin.focus();
	}