$_POST variables not stored when large file uploaded

Question

First off, I know similar questions have been asked, however mine doesn't appear to be a server-limited file size....

When using one page with the form below and attempting to send to another file containing the script, it works fine with small files (under 2MB). However, a slightly larger file (around 3MB) it appears to pass the $_POST variables correctly, but the script fails for some unknown reason. Finally, a test file of 9MB fails to send the $_POST variables at all and a print_r($_POST) shows each as undefined.

Here's the form:

<form enctype="multipart/form-data" id="formEditTAPPS" method="POST" action="scripts/editTAPPSprocess.php">
Page ID Number:  <? echo $id; ?>
<input type="hidden" name="id" value="<? echo $id; ?>" />
<br />
Page Title:  <input type="text" name="newPageTitle" value="<?php echo $row['title']; ?>" style="width:300px;" />
<br />
Number of Pages in PDF:  <input type="text" name="newNumberOfPages" value="<?php echo $row['num_pages']; ?>" style="width:30px;" />
<br />
TAPPS Category:
    <select name="newCategory">
        <? while ($row2 = mysql_fetch_array($data2)) {
            $catIDfromCat = $row2['cat_id'];
            $catName = $row2['cat_name'];
        ?><option value="<? echo $catIDfromCat; ?>" <?php if ($catIDfromPages==$catIDfromCat){echo "selected=\"selected\"";} ?> ><? echo $catName; ?></option>
        <? } ?>
    </select>
<br />
Last Updated:  <? echo $row['last_updated']; ?>
<br />
Display Order:  <input type="text" name="newDisplayOrder" value="<?php echo $row['display_order']; ?>" />
<br />
Existing PDF:  <a href="/files/tapps/<? echo $row['filename']; ?>" /><? echo $row['filename']; ?></a>
<br />
Upload a New PDF:  <input name="newPDF" type="file" />
<br />
<input type="submit" name="Submit" value="Update this TAPPS Page" style="margin: 20px 0 0 50px;" />

And here's the processing script:

include_once('../../../common/db/conn.php');     // Connect to the database
// Assigns the variables passed from the form.
$id = $_POST['id'];
$title = $_POST['newPageTitle'];
$num_pages = $_POST['newNumberOfPages'];
$cat_id = $_POST['newCategory'];
$display_order = $_POST['newDisplayOrder'];
$newPDF = basename($_FILES['newPDF']['name']);
// Try to upload the file...
$target = "../../../files/tapps/";
$target = $target . $newPDF;
if(move_uploaded_file($_FILES['newPDF']['tmp_name'], $target)) {
    // Saves the data into the correct database table.
    $sql = "UPDATE tapps_pages SET title='$title', num_pages='$num_pages', cat_id='$cat_id', display_order='$display_order', filename='$newPDF' WHERE id='$id'";
    // Verifies the database stores the form results and sends the user to the "Success" page.
    $result = mysql_query($sql);
    if($result) {
        echo "<meta HTTP-EQUIV=\"REFRESH\" content=\"0; url=../editTAPPSpage.php?id=$id&success=1\">";
    } else {
        echo "<br /><br />Bummer, something broke. &nbsp;&nbsp;&nbsp;&nbsp; =(<br /><br />";
        print_r($_POST);
    }
} else {
    //  Problem uploading the file
    echo "<br /><br />Looks like there was a problem uploading the TAPPS page... Better tell Kevin!<br /><br />He's going to want to know this info, so please copy and paste it into the email...<br />";
    print_r($_POST);
    echo "<br /><br />";
    print_r($_SERVER);
    echo "<br /><br />";
    print_r($_SESSION);
}

Sounds like a upload_max_filesize problem to me, but I've addressed that with a php.ini file:

memory_limit = 128M
max_execution_time = 600
upload_max_filesize = 50M
post_max_size = 64M

And phpinfo() shows that the change stuck, after a reboot of Apache.

Am I missing a setting that could cause a timeout or limit the file size to 2MB? Thanks in advance for any help!