[jQuery] Firefox only selecting first element with given class

[Phil]

I am having an issue in firefox 3.5.3 I am using the following
selector

    $("#arrivalAirport .arrival").hide('slow');

I have a set of radios wrapped in span tags with the class of arrival
as such
<div id="arrivalAirport">
  <span class="arrival"><input type="radio" name="arrivalAirport"
value="fortware" />Fort Ware</span>
  <span class="arrival" id="tskay"><input type="radio"
name="arrivalAirport" value="tsaykey" />Tsay Keh</span>
  <span class="arrival"><input type="radio" name="arrivalAirport"
value="princegeorge" />Prince George</span>
  <span class="arrival"><input type="radio" name="arrivalAirport"
value="smithers"/ >Smithers</span>
  <span class="arrival"><input type="radio" name="arrivalAirport"
value="deaselake" />Dease Lake</span>
  <span class="arrival"><input type="radio" name="arrivalAirport"
value="bobquinn" />Bob Quinn</span>
</div>
for some reason in Firefox the Jquery only hides the very first span
(fortware)  where as in IE it hides them all.

Is anyone aware of similar issues or do they have a fix?  I have also
tried selecting #arrivalAirport span which does not work either.