ie-warning.js

function setCookie(name, value) {
	if(name != '')
		today = new Date();
	expires = new Date(today.getTime() + (8 * 7 * 86400000)); 
	document.cookie = name + '=' + value + '; expires=' + expires;
}

function getCookie(name) {
	if(name == '')
		return('');

	name_index = document.cookie.indexOf(name + '=');

	if(name_index == -1)
		return('');

	cookie_value =  document.cookie.substr(name_index + name.length + 1, document.cookie.length);

	end_of_cookie = cookie_value.indexOf(';');
	if(end_of_cookie != -1)
		cookie_value = cookie_value.substr(0, end_of_cookie);

	space = cookie_value.indexOf('+');
	while(space != -1) { 
		cookie_value = cookie_value.substr(0, space) + ' ' + 
		cookie_value.substr(space + 1, cookie_value.length);
		space = cookie_value.indexOf('+');
	}

	return(cookie_value);
}

if (getCookie('warning_has_shown') != 'yes') {
	// your warning html url
	var warning_url = 'ie-warning.html';
	location.href = warning_url+'?return='+location.href;
}