http://jsfiddle.net/Brj8m/

if (props != null && props.value === null && !didWarnValueNull) {
    warning(
      false,
      '`value` prop on `select` should not be null. ' +
      'Consider using the empty string to clear the component or `undefined` ' +
      'for uncontrolled components.'
    );
    didWarnValueNull = true;
  }
}
var valuePropNames = ['value', 'defaultValue'];
/**
 * Validation function for `value` and `defaultValue`.
 * @private
 */
function checkSelectPropTypes(inst, props) {
  var owner = inst._currentElement._owner;
  LinkedValueUtils.checkPropTypes(
    'select',
    props,
    owner
  );
  if (props.valueLink !== undefined && !didWarnValueLink) {
    warning(
      false,
      '`valueLink` prop on `select` is deprecated; set `value` and `onChange` instead.'
    );
    didWarnValueLink = true;
  }
  for (var i = 0; i < valuePropNames.length; i++) {