Yahoo! Messenger Error: Locked Account?

I have been using Yahoo! Messenger for few years, and I got a problem using it yesterday. The error dialog box gave me message like this:

There was a problem signing you in to Yahoo! Messenger.
Your account has been locked. Please click “Forgot Password…” to start the unlocking process.  (81003003)

The problem was that I used it few hours before and everything was right. I’m using Yahoo! Messenger So, I tried to logged in to my Yahoo! account. Username and password combination did not work. Not good. I was sure that I put correct details. I tried again. And, it worked! And, when I went back to my Yahoo! Messenger and tried to log in, everything was back to normal. OK, there was a little problem there. Not sure what it was, but it’s fine now.