This run for me, try it.
'Not sure if I had the same problem, but try to open this page: http://www.facebook.com/username , go back to gwibber and use your username instead of your email when you login to your account. After that the Add button appeared for me.'
This run for me, try it.
'Not sure if I had the same problem, but try to open this page: http:// www.facebook. com/username , go back to gwibber and use your username instead of your email when you login to your account. After that the Add button appeared for me.'