Confused about BES and service plans

I'm taking the plunge into Crackberry land with a new 8820 or 8320 (can't quite make up my mind) to access my client's corporate Groupwise email. I'd like to get push email and all that other great stuff, but I'm confused since some of my provider's plans (Rogers) have BIS and others have BIS + BES.

I thought the way BES worked was that it was installed on my client's Groupwise servers somehow and would push emails to me, but maybe I need to buy a BES service plan from my provider to make that work? Any info would be helpful and I can't wait to join the ranks of Crackheads around the world! :)

In order to be on a company's BES server you need to have the BES plan (aka BES+BIS).

A device with a BIS only plan cannot be activated on a BES server.

You will need a BES data plan on your BB. Different providers are different so check with yours. Your clients need a BES server. BES Express is free and comes with 1 free license and each additional 1 is $99.00 and you can have up to 15 users on it before you need to upgrade your BES license.