setTabBox = function(tabs) { 
    this.ids = tabs;
}

changeTabBox = function(id){
    for(i in this.ids) {
        var tab = document.getElementById('tbTab-' + this.ids[i]);
        var box = document.getElementById('tbBox-' + this.ids[i]);
        if (this.ids[i] == id) {
            if (tab) tab.className = 'on';
            if (box) box.className = 'on';
        }
        else {
            if (tab) tab.className = '';
            if (box) box.className = '';
        }
    }
}