No, it should only say activating for a short period, immediately afterwards it should drop to a line that says "verifying encryption...". Once it gets past this stage it will actually give you a % of how close it is to finishing.

I have found that if you are in an exchange environment sometimes the accounts themselves are messed up when they get created. In this instance i simply delete the AD user account and completely remake it from scratch.

Scenario: BlackBerry says "Activating..." for longer then an hour then eventually times out and fails.

Fix: Recreate the AD/Exchange account by copying an account you know works for bb activation.