php $_POST array empty upon form submission

I have a custom CMS i've built that works perfectly on my dev box (Ubuntu/PHP5+/MySQL5+).

I just moved it up to the production box for my client and now all form submissions are showing up as empty $_POST arrays.

I found a trick to verify the data is actually being passed using file_get_contents('php://input'); and the data is showing up fine there -- the $_POST/$_REQUEST arrays are always empty.

I've also verified the content-type headers are correct as well via firebug (application/x-www-form-urlencoded; charset=utf-8).

This issue is happening regardless of whether a form is submitting via AJAX or a regular form submit.

Any help is greatly appreciated!

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