In Brazil, SMSes are paid by the sender at local rates. If you are roaming internationally you might pay for receiving them, but it has been a long time since I saw charges for receiving SMSes. Probably the carrier recoups the interconnection fees when you send a SMS back.

For calls, though, the caller pays local rates, but you will pay your share of the roaming charges. Some carriers on pre-paid plans charge you a national long distance fee per call too.