MS Exchange Team blogged about BlackBerry Enterprise Server support for Exchange 2010 recently. It has been viral on social networks and many have been cheering about the news as their Exchange 2010 deployment or upgrade plans hinged on this to some degree.

I was one of them. I was waiting for this news as it allows me to help customers I work with and plan accordingly.

As I started digging into details, I found few things that I didn’t necessary like.

  • I could not find any documentation on how BES connects to mailboxes, does it use RPC Service on CAS (MAPI on Middle Tier)?
  • Calendaring by default still uses MAPI/CDO libraries. You can configure BES to use EWS with provided Trait Tool, but I failed to understand the impact of doing so with available documentation
  • BES recommends to Turn off Client Throttling in Microsoft Exchange 2010!
  • BES recommends to Increase the maximum number of connections to use Address Book Service from default 50 to a large number (documented 100,000)!!!

Last two bullets in particular greatly concerns me as Exchange developers must have imposed default limits based on previous experiences and a good reason. By making BES recommended changes, are you going to open up a door to potential issues?

For enterprise clients, the road to implementing BES in Exchange 2010 environment, especially in coexistence scenario with Exchange 2003 and/or Exchange 2007 will require careful planning which isn’t going to be a fast track by any means.

It will be interesting to find out more details and assess the real impact of recommended changes.