All message will appear in the MESSAGES icon.
If you seperated SMS, that will appear in the SMS icon only.
Most people hide the individual mailbox icons, as the MESSAGES icon picks them all up.
You cant do anything about that.
You need to untick a box in the options of BBM to not have the messages go into the MESSAGES icon.
"That's it then. Cancel the kitchen scraps for lepers and orphans, no more merciful beheadings... and call off Christmas."