Como inhabilitar CAMBIO de OPTION en SELECT? (pero enviar VALOR !!)

[_cronos2]

Código HTML:

<form method="get" action=''>
 <select name="zzz" onchange='noCambia(this);'>
  <option value="111">111</option>
  <option value="222" selected="selected">222</option>
  <option value="333">333</option>
 </select>
 <input type="submit" value='Enviar' />
</form>
 

Código Javascript:

function noCambia(select){
 if(select.selectedIndex!=1){
  select.selectedIndex=1;
 }
}
 

Saludos (: