index of $_POST seemingly empties at random - php

Question

Ok so this is driving me insane! I've got a script written that takes user submitted product information from a previous page and sends it to the user's facebook business page via the facebook php sdk.
Here's the php code:
$app_id = "1234567890";
$app_secret = "1234567890";
$page_id = "1234567890";
$page_token = "1034921234567890";
$store_name = "MyStore.com";
$store_url = 'http://www.mystore.com';
$cur = '$';
$new_message = "New Product!";
$prod_image = $store_url . "/images/" . $_POST['products_image'];
$price = $products_price;
$prod_url = $store_url . '/index.php?main_page=product_info&cPath=' . $current_category_id . '&products_id=' . $products_id;
$prod_name = $_POST['products_name'][1];
$prod_description = $_POST['products_description'][1];
include_once 'facebook/facebook.php';
$facebook = new Facebook(array(
'appId' => $app_id,
'secret' => $app_secret,
'cookie' => true, ));
$attachment = array(
'access_token' => $page_token,
'message' => $new_message,
'name' => $prod_name,
'link' => $prod_url,
'caption' => 'Price: '.$cur . $price,
'description' => $prod_description,
'picture' => $prod_image
);
Everything sends to facebook fine except on some servers$prod_description aka $_POST['products_description'][1] ends up empty. When a var_dump($_POST['products_description']); is placed on the same line, it comes back with:
array(1) { [1] => string(35) "This is a
test product description." }
So I know the information is there and not being overwritten it's just for whatever reason when sent to facebook (with cURL from the include_once file) it doesn't post.
I should also say that this is a Zen Cart mod that is available for download and I while haven't been able to reproduce the error myself (test on 4 different servers) I have had miltiple users add the var_dump and send me the results.
I guess my question is; Is there something (like a ini setting, cURL option, etc) that may vary from server to server that would cause random indexes to empty when sent via cURL and is there something I can do to fix it?
Thanks in advance.

Answer 1

I think problem is in the way data is passed. You have spaces in the description, that can cause problems...
Try explicitly setting enctype for the form to "application/x-www-form-urlencoded"
<form enctype="application/x-www-form-urlencoded" .... >
You can also try to url_encode the product description before passing it to Facebook.
$prod_description = urlencode($_POST['products_description'][1]);