Jquery Form-Plugin doesn't get Submit - Basic understanding

I know there are several threads about this topic but I couldn't find one to fit my needs.

I'm simply trying to sand an form asynchronous using the jQueryFormPlugin.

I've got this basic form in index.php

<form id="test_form" action="http://127.0.0.1/MwebCms/index.php?admin=1&p=navigation&add=1" method="POST">
<table>
    <tr>
        <td>Title</td>
        <td><input type="text" name="title"></td>
    </tr>
    <tr>
        <td></td>
        <td><input type="submit" value="Speichern" name="submit"></td>
    </tr>
</table>
</form>

Now after including Jquery and the Jquery form plugin I added this in my JavaScript file:

$(document).ready(function() { 
        $('#test_form').ajaxForm(function() { 
            alert("test"); 
        }); 
    }); 

Now that's all fine and dandy, but if I now check in index.php for:

echo $_POST["title"];

It will never be set.

What am I doing wrong or is my basic understanding of the jqueryFormPlugin completely wrong at all?

Source: http://malsup.com/jquery/form/#getting-started

I found the mistake I made:

The $_POST was sent alright, but it wasn't displayed. After changing the jquery to the following:

$(document).ready(function() {
$('form').ajaxForm(function(data) { 
    $("body").html(data);
});
});

It all worked properly.