What is Lionel messi Twitter?

On the twitter site, there is an account that seems to be the account of Messi. The name of the account is : imessi

, BUT

FIFA decided that no one, who plays at the WC2010, is allowed to use twitter during the tournament.

When we look at the ''account'' of Messi, we can surely see that he has sent a tweet on June 20th.

That is a contradiction, isn't it? (So it seems that the account, we refer to the account of Messi, may be an account that is used by someone else)

Cheers