I don't think the Blackberry texting service (do they call it BBS or something) will work with PetroCanada's service. Can't you just send ordinary text messages that all other phones can do? Surely your Samsung phone can send text messages.
In order to get internet access, you have to subscribe to the service. It will be an $8 add-on to your present monthly plan. Then you have to set up the correct APN info on your phone.
(I'm a Speakout user, not PetroCanada, so I'm making assumptions here.)