Malsup's jQUery Form plugin - how to submit only PART of a form.

Malsup's jQUery Form plugin - how to submit only PART of a form.

Malsup's most excellent and comprehensive Form plugin has me completely stuck on just one thing.
Take a look at this:

At the bottom are a variety of submit buttons, and when you click one, it knows which one has been clicked.
And I've been through the js and the source and the examples and I can't figure out how the bleep it's done!

I'll tell you why I'm asking, then perhaps you can probably tell me I'm doing it wrong anyway!
Let's say a blind person logs in, and want to edit their presets.
I don't want the form to be too complex or clever or ajaxy, as screenreaders don't like that, so it just iterates through as many presets as they have, and populates a form with edit boxes.
But there's no point "pushing back" 29 unchanged items just to edit one row.

So my idea was I'd just "fieldSerialize()" the details of the row that was currently being edited and submit that to my little php routine that updates the db. Then they can do a refresh just to hear the list again.

The js looks like:

  1. $(document).ready(function() {
  2.     $('#myForm').ajaxForm(function() {
  3.       var queryString = $('#myForm').formSerialize();
  4.      $('div.thequery').text(queryString);
  5.      $.post('scorewriter.php', queryString); 
  6.     });
  7. });

All works fine like that. But if I change line 3 to:
var queryString = $('#myForm :button').fieldSerialize();
it doesn't work. I've also tried:

'#myForm :button' 
'#myForm .button'  
'#myForm :input' 
'#myForm .input'

and even though the DOM inspector tells me that the button is called "input", Firefox complains of "unknown name or pseudo-class".

BTW, the html looks like this

  1.   <form id="myForm" action="scorewriter.php" method="post">
  2.   Preset 1  <input type="text" size="30" id="preset1" name="preset1" value="Easy Listening" />
  3.   <input type="text" name="url1" size="50" value="" />
  4.   <input type="submit"  name="submitButton" value="Submit1" /><br />
  5.   Preset 2  <input type="text" size="30" id="preset2" name="preset2" value="Smooth Jazz" />
  6.     <input type="text" name="url2" size="50" value="http://www.somethingelse" />
  7.     <input type="submit"  name="submitButton" value="Submit2" /><br />
  8.   <input type="submit" value="Submit Comment" />
  9. (etc etc up to however many they have)
  10.   </form>                      
  11.   <div class = "thequery">query
  12.   </div>
(that last bit is just so I can test what I think I've just done).

Maybe I should just generate as many separate forms as there are presets, but then I'm going to need as many ready(function)'s as there are rows, which is going to be very messy.