function getElementsByClass(searchClass, domNode, tagName) {
            if (domNode == null) domNode = document;
            if (tagName == null) tagName = '*';
            var el = new Array();
            var tags = domNode.getElementsByTagName(tagName);
            var tcl = " " + searchClass + " ";
            for (i = 0, j = 0; i < tags.length; i++) {
                var test = " " + tags[i].className + " ";
                if (test.indexOf(tcl) != -1) el[j++] = tags[i];
            }
            return el;
        }

        function doIt() {
            var elms = getElementsByClass('blink');
            for (i = 0; i < elms.length; i++)
                elms[i].style.visibility = (elms[i].style.visibility == "hidden") ? "visible" : "hidden";
        }

        function Knipper() {
            setInterval('doIt()', 1000);
        }
        window.onload = Knipper;