Thunderbird and Multiple accounts

I am trying to use Thunderbird, and have downloaded the latest release (v2.0.0). I have setup four different email accounts and all of them work fine. I can read/send emails from each account.

Is it possible to set up TB such that:
When I try to look at email-acct's email, it asks for password (not the password on email server), only once, like Outlook Express does for identities?

tia
-H