Auth systems/OAuth/Library

http://pear.php.net/package/HTTP_OAuth
 * New BSD License
 * last update 2011-07-16

PECL Extension
 * last updated 2012-10-01
 * "This pecl package is considered the de facto standard by Rasmus Lerdorf."

http://code.google.com/p/oauth-php/
 * MIT License
 * Last update Nov 2010

https://github.com/EHER/OAuth
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