Remember that sharing accounts isn’t just a violation of the terms, which could get you banned, it’s actually not a good thing to do in general. People can get details about you or content from you, or try to take action against you when you do something like that. It is your responsibility to keep your account information safe. Regarding the COD4 beta, the best advice I can give in a situation like this is try and be patient. We know you all want to play, and we think that’s great, but if you break the rules, you can be banned.
I hope this clears things up.