How to use Yahoo!7 Messenger for SMS
Pricing details
Carrier charges may apply for sending or receiving text messages. Check your wireless plan for details.
Signing out:
(1.1) Using text messaging, address a text (SMS) to one of the codes below depending on your carrier:Carriers Code Optus 2277 Telstra 019834 Vodafone 126007 
(1.2) Then, text: out.
(1.3) Select Send/OK.NOTE: Some carriers will send you a text message confirmation that you are signed out of Yahoo!7 Messenger for SMS. To sign back in, see Sign in from your phone.
Yahoo!7 Messenger for SMS is currently available in the following countries: See countries
Americas: