Sends a new direct message to the specified user from the authenticating user.
sendDMbyId( $user_id, $text )
The user ID of the recipient user.
In case you want to specify the screen name of the recipient user, you can use Tuitter::sendDM method instead.
The text of your direct message. Keep it under 140 characters.
Returns Tuitter_DM object which has been just sent.