"jQuery serializeArray: Why Not An Associative Array?"

I'm trying to examine and modify form variables from jQuery by catching the submit event. jQuery has a serializeArray method that hands you the form variables in a nice array. For example:

    $('#someform').submit( function() {
        $.post("/some/url/", $(this).serializeArray(),
            function(data){
                console.log(data);
            }, "json");
        return false;
     } );

This is great, but the result of serializeArray is an integer indexed array whose values are (key,value) pairs. Eg.

    var data = $(this).serializeArray(),
    console.log( data[0] );
>> output: Object name=somename value=537

I'm wondering why the array looks like this, instead of being a dictionary (associate array, hash, or whatever you want to call it) such that the keys are "name"s and values are "value"s. Eg.

    var data = $(this).serializeArray(),
    console.log( data.somename );
>> output: 537

Anybody know the answer?