1. This trick is now public, don’t expect it to be working forever. Just be quick and achieve glory.
2. Now, Navigate to - http://www.orkut.com/Invite.aspx.
3. Now Enter Email Addresses to add as your friend(s) - Make sure the members are active on orkut.
4. Enter the captcha.
5. Submit
6. Now, You will see option to add the profiles as your friend just select all the check boxes and all the profiles will be sent request automatically.

Regards