Web Callback appears as unlicensed when it is licensed.

Unable to use Web Callback. "This feature is currently not licensed. For more information on this feature or to purchase this Add-On, please see the information below."

The only thing I see when navigating to Web Callback is:
==> /var/log/asterisk/freepbx_dbug <==
2015-Mar-24 08:15:12 /var/www/html/admin/modules/endpoint/functions.inc.php:62
[NOTICE]: Use of undefined constant endpoint_check_license - assumed 'endpoint_check_license'

2015-Mar-24 08:15:12 /var/www/html/admin/modules/endpoint/functions.inc/functions_common.php:11

true

2015-Mar-24 08:15:12 /var/www/html/admin/modules/webcallback/views/page.webcallback.php:26
[NOTICE]: Undefined variable: webcallback_licensed

2015-Mar-24 08:15:12 /var/www/html/admin/modules/webcallback/views/index.php:7
[NOTICE]: Undefined variable: modname

2015-Mar-24 08:15:12 /var/www/html/admin/modules/sysadmin/functions.inc/sales.php:33
[NOTICE]: Undefined variable: html

Note that this "seems" to affect all versions 2.11 and forward.