Managing the callback feature
You can permit BlackBerry® Mobile Voice System users to use the callback feature to make outgoing calls and help your organization save on call charges. For example, if a user will be making calls from a location where it is more expensive to make calls than to receive calls, you can use the callback feature so that the user has access to your organization's local, long-distance, and international calling rates.
To use this feature, you must reserve an additional DID number for each user. A user calls the DID number and after hearing ringback, the user ends the call. The BlackBerry MVS Server then calls the user at the specified phone number. After the user answers the call from the BlackBerry MVS Server, the user hears a dial tone and can make outgoing calls. A user can use the callback feature from any phone.