init(linkBehaviour);
//alert('linkBehaviour');

function init(func)
{
    //alert('init');
    var oldonloadspt = window.onload;
    if (typeof window.onload!='function')
    {
        window.onload = func;
    }else{
        window.onload = function() {
            if (oldonloadspt){
                oldonloadspt();
                }
            func();
            }
    }
    
}

function linkBehaviour()
{
    //return for browsers that don't support the DOM
    if (!document.getElementsByTagName) return;
    var anchors = document.getElementsByTagName("a");
 
    for (var i=0;i<anchors.length;i++)
    {
        var anchor = anchors[i];
        if(anchor.className == "external")
        {            
            //var oldscript = anchor.onclick;
            anchor.onclick = function() {
                //if(oldscript)
                //    oldscript();
                return alert('You are now leaving portmantravel.com.');
                }
        }
    }
}