Wordpress Plugin NOT activating

Hi am having a problem with activating a wordpress plugin when i try to it triggers the following error.

The error is as follows:

Plugin could not be activated because it triggered a fatal error.

Parse error: syntax error, unexpected T_FUNCTION, expecting ')' in /home4/connectm/public_html/wp-content/plugins/upme/modules/social/lib/facebook_SDK/autoload.php on line 45

My PHP Version is :PHP Version 5.2.17

The code is as follows:

<?php

if (version_compare(PHP_VERSION, '5.4.0', '<')) {
    throw new Exception('The Facebook SDK requires PHP version 5.4 or higher.');
}

line 45 below...

spl_autoload_register(function ($class) {

Line 46 below

// project-specific namespace prefix $prefix = 'Facebook\';

    // For backwards compatibility
    $customBaseDir = '';
    // @todo v6: Remove support for 'FACEBOOK_SDK_V4_SRC_DIR'
    if (defined('FACEBOOK_SDK_V4_SRC_DIR')) {
        $customBaseDir = FACEBOOK_SDK_V4_SRC_DIR;
    } elseif (defined('FACEBOOK_SDK_SRC_DIR')) {
        $customBaseDir = FACEBOOK_SDK_SRC_DIR;
    }
    // base directory for the namespace prefix
    $baseDir = $customBaseDir ?: __DIR__ . '/';

    // does the class use the namespace prefix?
    $len = strlen($prefix);
    if (strncmp($prefix, $class, $len) !== 0) {
        // no, move to the next registered autoloader
        return;
    }

    // get the relative class name
    $relativeClass = substr($class, $len);

    // replace the namespace prefix with the base directory, replace namespace
    // separators with directory separators in the relative class name, append
    // with .php
    $file = rtrim($baseDir, '/') . '/' . str_replace('\\', '/', $relativeClass) . '.php';

    // if the file exists, require it
    if (file_exists($file)) {
        require $file;
    }
});

via Chebli Mohamed