function setCookie(name, value, expires, path, domain, secure) {
	var today = new Date();
	today.setTime( today.getTime() );
	if ( expires ) {
		expires = expires * 1000 * 60 * 60;
	}
	var expires_date = new Date( today.getTime() + (expires) );
	document.cookie = name + "=" +escape( value ) +
	( ( expires ) ? ";expires=" + expires_date.toGMTString() : "" ) + 
	( ( path ) ? ";path=" + path : "" ) + 
	( ( domain ) ? ";domain=" + domain : "" ) +
	( ( secure ) ? ";secure" : "" );
}

function getClickThru() {
	if (document.referrer != "" && document.referrer.indexOf(document.domain) == -1 && document.location.toString().indexOf('https://') == -1)  {
		setCookie('ref',document.referrer,2,'/','','');
	}
}

getClickThru()