In response to my post about running your own email server, a reader mentioned the BlackBerry mobile email service. According to his computer consultant, running Exchange (Microsoft's messaging and collaboration software) as an in-house email server is necessary for the BlackBerry. Coincidentally, this subject came up with three other clients over the past year so there's obviously another common misunderstanding here—they were going to install a company server for the same reason.
The consultant was partly correct, but it really depends on your needs. BlackBerry has two types of solutions: