window.onload = function() {
    // Code if document.getElementByClassName() doesn't exist
    if (document.getElementsByClassName == undefined) {
        document.getElementsByClassName = function(className) {
            var hasClassName = new RegExp("(?:^|\\s)" + className + "(?:$|\\s)");
            var allElements = document.getElementsByTagName("*");
            var results = [];

            var element;
            for (var i = 0; (element = allElements[i]) != null; i++) {
                var elementClass = element.className;
                if (elementClass && elementClass.indexOf(className) != -1 && hasClassName.test(elementClass))
                    results.push(element);
            }

            return results;
        }
    }

    var anchorList = document.getElementsByClassName('targetblank');
    for (var i in anchorList) {
        anchorList[i].target = '_blank';
    }
}