try {
        comment = "adding two numbers";
        var a = 2+2;
        
        comment = "saying hello";
        var hello ="hello";
        alert(hallo);

    } catch (e) { alert("while "+comment+": "+e.description); }

var reportStatus = new Array();
function report ( msg ) {
    reportStatus.push ( msg );
}
function showReport ( ) {
    alert ( reportStatus.join ( "\n" ) );
}
window.onerror = function ( err, url, line ) {
    report ( err + " [" + url + " - line " + line + "]" );
    showReport();
}

-- MattWalsh - 03 Sep 2006