function new_window(id) {
   var n_window = window.open('http://www.tvg.at');
   n_window.focus();
   document.getElementById(id).removeAttribute('href');
}

function add_window_event() {
    var links = document.getElementsByTagName('a');
    var numlinks = links.length;
    for(var i = 0; i < numlinks; ++i) {
        if(('klima' == links[i].id) || ('klima2' == links[i].id)) {
            links[i].onclick = function() {
                new_window(this.id);
            }
        }
    }
}

add_onload_handler(add_window_event);