function intercetta() {
    var regex = new RegExp("(^|\\s)blank(\\s|$)");
    for (var i = 0; i < document.links.length; i++)
        if (regex.test(document.links[i].className))
            document.links[i].target = "_blank";
    for (var i = 0; i < document.forms.length; i++)
        if (regex.test(document.links[i].className))
            document.forms[i].target = "_blank";
}

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

addLoadEvent(intercetta);