var om = {

  createSelectOptions: function(selectFieldId, newOptions, optionsOffset){
    var selectField = document.getElementById(selectFieldId);

    if(!optionsOffset){
      var optionsOffset = 0;
    }

    var i;
    for(i = optionsOffset; i < selectField.options.length; i++){
      selectField.options[i] = null;
      --i;
    }
    jQuery.each(newOptions, function(key, value) {
      if(typeof value == "string")
      {
        var opt = new Option(value, key);
        selectField.options[selectField.length] = opt;
      }
      else
      {
        var optgroup = document.createElement('optgroup');
        optgroup.label = key;
        var opts = new Array();
        jQuery.each(value, function(k, v) {
          opts.push(new Array(v, k));
        });
        for(var i  in opts){
          var opt = new Option(opts[i][0], opts[i][1]);
          optgroup.appendChild(opt);
        }
        selectField.appendChild(optgroup);
      }
    });
  }

}