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

        function doPopups () {
                var links = document.getElementsByTagName('a');
                for(var i = 0; i < links.length; i++) {
                        if(links[i].className == 'popup') {
                                links[i].rel = links[i].href;
                                links[i].href="#";
                                links[i].onclick = function() {
                                        var url = this.rel;
                                        var controls = 'width=750,height=500,menubar=yes,location=yes,resizable=yes,scrollbars=yes,status=yes';
                                        window.open(url, 'windowname', controls);
                                }
                        }
                }
        }

        addLoadEvent(doPopups);