New to groups and don't know whether this has already been asked

My company runs Small Business Server 2003 and I've just won a
Blackberry 7100v. Do I need to install Blackberry Enterprise Server to
retrieve my e-mails or can I retrieve using Outlook Web Access?

All the re-sellers that I speak to tell me I need BES but the
Blackberry web site shows Outlook Web Access as being a compatible
e-mail account.

Any suggestions etc would be much appreciated.

Many thanks

Paul Hine