Problems with not validated users

Hi guys! I´m new at Elgg and the Forum. First of all, I need to ask you to please forgive my english mistakes. ^^

Now I have a problem, in my elgg website (http://www.ptce2.iff.edu.br/redesocial/), the users have to be adm validated so they can join in and etc... But several users started to join without that need. They look like bots...

I have tried to use the latest version of the pluggins and elgg itself.

Tried to install it again on server.

Asked my adm to change their passwords.

BUT the problem is still there.

I have screenshots to show you that no adm is validating them. Take a look: <a href="http://www.freeimagehosting.net/bb57e"><img src="http://www.freeimagehosting.net/t/bb57e.jpg"></a&gt;

 

Thank you for the support, if need more info, mail me at luiz.g.s.silva@hotmail.com