排序simpleXML对象

Question

I have a problem to sort array of SimpleXMLElement Object. The data is:

[ServiceHotel] => Array
(
  [0] => SimpleXMLElement Object
    (
      [@attributes] => Array
        (
          [availToken] => 0
        )
    )
  [1] => SimpleXMLElement Object
    (
      [@attributes] => Array
        (
          [availToken] => 1
        )
    )
  [2] => SimpleXMLElement Object
    (
    [@attributes] => Array
        (
          [availToken] => 2
        )
    )
  [3] => SimpleXMLElement Object
    (
      [@attributes] => Array
        (
          [availToken] => 3
        )
    )
)

I want to sort that data, order by availToken in PHP. Can anybody help me?