In the method below, the $language variable isn't defined. I believe it should be set to $current_language. (SampleLicenseAddon)

  protected static function loadLicenseStrings()
    {
        global $sugar_config, $currentModule;

        //load license config file....if it isn't broken don't fix it
        $default_language = $sugar_config['default_language'];

        $langs = array();
    **  if ($language != 'en_us') { **
            $langs[] = 'en_us';
        }
        if ($default_language != 'en_us' && $language != $default_language) {
            $langs[] = $default_language;
        }
        $langs[] = $language;