The 7100i does not have the ability to send SMS. However, sending an MMS message with only text has the same effect. You will be charged the SMS rate for MMS messages that only include text.
Also, your BB Data Plan does not cover sending/receiving SMS/MMS messages. You will be charged per message unless you have a text messaging plan.
You can get free outgoing SMS messages by sending them via email to
. Substitute the number with whoever you're trying to send the SMS to.