Centos – Trying to install phptheadmin – getting error 500

(Using PHP 5.4.15, Apache 2.2, CentOS 6.4 minimal)

I'm having trouble installing phpMyadmin, I followed the instructions here, specifically:

1. I uploaded the phpMyAdmin-*.tar.gz & unzipped it to /var/www/html/phpmyadmin/

2. Copied config.inc.php & CHMODed it to 600 (I have suexec enabled, though I also tried with 660)

Yet I'm having error 500 whenever I access http://my-ip-address/phpmyadmin/index.php

I checked the apache2 logs, I see this error repeated countless times:

[Fri Jun 07 00:24:26 2013] [error] [client 11.222.33.44] PHP Fatal error: Call to a member function get() on a non-object in /var/www/_/8thpixel.com/public_html/phpmyadmin/libraries/Header.class.php on line 135

I checked the source of Header.class.php (didn't modify it), line #135 looks like this:

if ($GLOBALS['PMA_Config']->get('user_preferences') == 'session'
&& ! isset($_SESSION['userprefs_autoload'])

I checked $GLOBALS, there's no user_preferences at all!

I've been pulling my hear for two days now, anyone can tell me what's wrong anyway?