Hi, newbie here. My problem is that my phone starts trying to send MSM at 6 am or late at night. This messages appear in the outbox. Thay can never be send and my phones starts giving messages of being unable to send that message.

Another thing is that, even though my bluetooth is turned off, my phone starts sending messages via BT and even .sis files.

Sometimes when i look at my phone it has a message saying something like "BT server closed"

Hope you can help

Sounds like you (or someone else while you were not looking) has installed a malicious app (some would call it a "mobile virus") on your 6600. Reformat the phone to clean it:
http://www.allaboutsymbian.com/forum/showthread.php?t=17507

Thanks it really helped me out!