1. A wireless handheld communications device, comprising: a first volatile memory having a first maximum bound buffer size; a second volatile memory having a second maximum bound buffer size; a non-volatile memory; and a processor adapted to control data transfer between the first volatile memory, the second volatile memory, and the non-volatile memory wherein, responsive to an incoming message size exceeding or being equal either the first volatile memory first maximum bound buffer size or the second volatile memory second maximum bound buffer size, the processor is structured to store an e-mail message in one of the first and second volatile memories.