Displaying reCAPTCHA with JavaScript and verifying using PHP

Question

I have a site that uses SSI for the headers and footers of the page.

I've created an AJAX request that sent all of the form data to a script on the server that would verify the form and the reCAPTCHA all in one.

I have run into one small problem though. I have been forced to use plain HTML to display the reCAPTCHA due to the fact that all of the file extensions are shtml.

The PHP verification plugin is throwing a fit and telling me "invalid-request-cookie."

I have checked and double checked all of the keys and the only thing that I can come up with is that the request does not like the fact that I am using HTML for displaying the reCAPTCHA and the PHP plugin for verifying it.

I have researched forcing my server to parse the PHP in shtml files so I can display the reCAPTCHA with PHP but due to the fact that the server is a GoDaddy IIS7, that seems to be impossible.

My question is two-fold:

1. Is what I suspect indeed my problem?

2. If so, is there any way around this?

Here is my HTML/JavaScript:

    <div id="recaptcha-widget">
        <script type="text/javascript" src="http://www.google.com/recaptcha/api/challenge?k=public_key_WAS_inserted_here">
                </script>
                <noscript>
            <iframe src="http://www.google.com/recaptcha/api/noscript?k=public_key_WAS_inserted_here"
                    height="300" width="500" frameborder="0"></iframe><br>
            <textarea name="recaptcha_challenge_field" rows="3" cols="40"></textarea>
            <input type="hidden" name="recaptcha_response_field" value="manual_challenge">
        </noscript>
    </div>
    <p style="padding: 0 45%">
        <input type="submit" value="Submit" id="submit-button">
    </p>

And here is the JavaScript AJAX request to my PHP validation script.

    var dataToSend = $('form #contactForm').serialize();

    if($('#contactForm #response').hasClass('error') === false){
        jQuery.ajax({

            type: 'POST',
            url: '../contact.php',
            data: dataToSend,
            cache: false,
            beforeSend: function(){
                $('#contactForm #response').show().removeClass().addClass('sending response').html("Sending email.  Please wait...");
            },
            error: function(){
                $('#contactForm #response').show().removeClass().addClass('error response').html("Internal error.  Please try again.");
            },
            success: function(response){
                if (response !== "The recaptcha response was invalid.  Please try again."){
                $('#contactForm #response').show().removeClass().addClass('error response').html(response);
                } else {
                    $('#contactForm #response').show().removeClass().addClass('success response').html(response);
                }
            },
            timeout: 20000

        });
    }

And here is the PHP validation script. I do have the recaptchalib.php on my server.

    <?php
    require_once('recaptchalib.php');
    $privatekey = "privatekey_WAS_inserted_here";
    $resp = recaptcha_check_answer ($privatekey,
                                    $_SERVER["REMOTE_ADDR"],
                                    $_POST["recaptcha_challenge_field"],
                                    $_POST["recaptcha_response_field"]);

    if (!$resp->is_valid) {
    die ("The reCAPTCHA wasn't entered correctly. Go back and try it again." .
        "(reCAPTCHA said: " . $resp->error . ")");
    } else {
        // My verification on this side.  This part of the if/else never runs.
    }
    ?>

SOLVED: So I figured out my own problem. In my JavaScript, I was not sending the actual values for the challenge and response fields for the recaptcha. So I fixed that and the reCAPTCHA works flawlessly.