function externalLinks()
{
    if (!document.getElementsByTagName) return false;
    var anchors = document.getElementsByTagName("a");
    for (var i = 0; i < anchors.length; i++)
    {
        var anchor = anchors[i];
        if (anchor.getAttribute("href") && (anchor.getAttribute("rel") == "nofollow" || anchor.getAttribute("rel") == "external" || anchor.getAttribute("rel") == "external nofollow"))
        {
            anchor.target = "_blank";
            if (!anchor.className)
            {
                anchor.className = "external";
            }
            else
            {
                newClassName     = anchor.className + " external";
                anchor.className = newClassName;
            }
        }
    }
}

function addLoadEvent(func)
{
    var oldonload = window.onload;
    if (typeof window.onload != 'function')
    {
        window.onload = func;
    }
    else
    {
        window.onload = function()
        {
            oldonload();
            func();
        }
    }
}

addLoadEvent(externalLinks);