As of today – 17 of june 2013 – I have removed this security setting, – because I have now found another well working solution.
For the time being though, we still keep up the procedure of all new users having to be approved by admin on registration. This may also in time not be needed, however it is only of little inconvenience, – so I hope it is okay for now.
And any new member / user can now write in forum without having to wait for approval.