function sendpopunder()
{
var cookievalue = ReadCookie ("siteid")

        if (window.name != 'TCFBPop' && cookievalue != tcfb_id) {
var expiredate = new Date ();
//cookie expires in one hour

expiredate.setTime (expiredate.getTime() + (1000 * 60 * 60));
//set the cookie
setcookie("siteid",  tcfb_id, expiredate);

LeftPosition = (screen.width) ? (screen.width-750)/2 : 0;
TopPosition = (screen.height) ? (screen.height-450)/2 : 0;
settings ='height=450,width=750,top=0,left='+LeftPosition+',toolbar=yes,menubar=yes,scrollbars=yes,status=yes,resizable=yes,status=yes,location=yes'

         var display = 'http://www.tcfb.com/includes/exit.php?id=' + tcfb_id;
         popwin=window.open(display,'TCFBPop',settings);
         popwin.blur();
         window.focus();
         return true;

        }
}

function setcookie(name, value, expires){

     if (!expires) expires = new Date();
         document.cookie = name + "=" + escape (value) + "; expires=" + expires.toGMTString() +  "; path=/";

}

function ReadCookie (name) {
         var dcookie = document.cookie;
         var cname = name + "=";
         var clen = dcookie.length;
         var cbegin = 0;
             while (cbegin < clen) {
             var vbegin = cbegin + cname.length;
                 if (dcookie.substring(cbegin, vbegin) == cname) {
                 var vend = dcookie.indexOf (";", vbegin);
                     if (vend == -1) vend = clen;
                 return unescape(dcookie.substring(vbegin, vend));
                 }
             cbegin = dcookie.indexOf(" ", cbegin) + 1;
                 if (cbegin == 0) break;
             }
         return null;
         }

document.onunload=sendpopunder;
window.onunload=sendpopunder;