It depends on what the xxx is on each of your 4.6.0.xxx's. At some point after your OS version, this new feature was added.
You would have to upgrade your OS to, at minimum, the lowest version that introduced this feature. If your xxx is the lowest of yourself and your two friends, that would confirm it for the most part.
Supervising Manager of the Department of Redundancy Department.
BlackBerry Certified Support Specialist