Hi! PIN messages (used by BB Messenger) work in the normal two-way mode (able to send and receive) just between Blackberry devices. If you use BlackBerry Connect on Nokia E51 for instance, you are able just to receive PIN messages, but not to send them, so it's one-way messaging only. I assume it's the same with the E61. As I said, if you need two-way PIN messages, you have to use a BlackBerry device. Hope this helps.