function changeJourney( currObj )
{
  switch(currObj.value)
  {
    case "R" : document.FlightForm.RetDate.value = "dd/mm/yyyy"
               document.FlightForm.RetDate.disabled=false
               break
    case "O" : document.FlightForm.RetDate.value = ""
               document.FlightForm.RetDate.disabled=true
               break;
  }  
}