function ToggleDestinationPropertyDropdowns()
{
  var cboDestination = document.getElementById("ctl00_cphBody_ucReservationForm_cboMultiPropertyGroup");
  var cboProperty = document.getElementById("ctl00_cphBody_ucReservationForm_cboMultiPropertyProperty");
  var sDestinationValue = cboDestination[cboDestination.selectedIndex].value;
  var sPropertyValue = cboProperty[cboProperty.selectedIndex].value;
  if (sDestinationValue == "" && sPropertyValue == "")
  {
    cboDestination.disabled = false;
    cboProperty.disabled = false;
  }
  else if (sDestinationValue != "")
  {
    cboProperty.disabled = true;
    cboProperty.selectedIndex = 0;
  }
  else if (sPropertyValue != "")
  {
    cboDestination.disabled = true;
    cboDestination.selectedIndex = 0;
  }
}