Getting redirected to Page not Found when adding to shopping cart

[diego.s.v]

I'm having this issue and I already know the crupt, but still couldn't find a solution.

Open the file includes/functions/functions_general.php
Inside the function zen_redirect - line 37 paste the following:

echo '<pre>';
print_r($url);
print_r(debug_backtrace());
print_r($_SERVER);
print_r($_SESSION);
die();

Then go to your the product's page
e.g
http://www.yourstore.com/index.php?m...oducts_id=8671

Clear your browser cache, reload the product's page (don't go to other pages) and try adding the product to your cart.
See if you get a redirect from line 33 of the file init_sanitize.php