[jQuery] using jqueryimpromptu plugin and submit with validation

[K Bouton]

I am a jquery newbie who is trying to use the jquery impromptu plugin
to create an "ok/Cancel" button which does some validation before it
submits.
I currently have a working form which uses a standard javascript
confirm prompt - but I want it to be fancier -smile.
This is what I have - how do I convert it to the impromptu plugin?
Thanks
[code]
in header javascript...

function CheckYears(form) {
  var year = form.elements['year[]'];
  var numyearSelected = 0;
  for (var i = 0; i < year.length; i++) {
    if (year[i].selected) numyearSelected++;
  }
  if (numyearSelected == 1 && year.selectedIndex==0)   {
    return confirm('Are you sure you want to search on ALL Years?\r
\nIt may take a while.\r\nClick "OK" to search or "Cancel" to start
again.');
  }
}
[/code]
in body
[code]
form name="queryForm" action="test.php" method="POST"
onSubmit="return CheckYears(this)">
    <select name="year[]" multiple="multiple" size="12">
      <option selected="selected" value="All">All Years</option>
     <option value="2007">2007</option>
   ... etc
</selected>
<input type="submit" name="submit" value="Search  Availability"/>
  </form>
[/code]

I know it has something to do withthecallback function - but I can't
get it to work...