ok, i work for sprint and i know exactly what they are referring too. usually it is going to be a variant of your company.com/exchange(for OWA before 2007) and company.com/owa(for OWA 2007+). i cant give a SPECIFIC example but if you google for Outlook Web Access you will see what i mean.
But as you have already stated, if you have already talked with your IT and they said they specifically cannot give out the OWA site without approval AND the fact you have to have an OWA account created means unfortunately you would not be able to integrate your exchange email into a blackberry web client.
Blackberry Web Client USED to have a application that would sort of "search for the exchange server", but it was being found to work poorly, and was done away with.
You have TWO options from what I can see that you could do to integrate your email. Option ONE is attempt to use Desktop Redirector. I PERSONALLY DISLIKE THIS METHOD FULLY. It's a PAIN to use since you have to keep your desktop running with outlook/redirector to receive email, you CANNOT RECEIVE ATTACHMENTS through this way, and it's near IMPOSSIBLE to ever get this thing working when it stops.
DO THIS. Setup your web client account if you haven't already. Setup a Blackberry address. Now, go into your email settings for that address, and set the REPLY TO as your work address . To complete this setup, IT IS BEST TO REQUEST YOUR IT DEPARTMENT TO SETUP A HARD FORWARD ON THE SERVER TO FORWARD TO THAT SPRINT.BLACKBERRY.NET ADDRESS.
You may run into a brick wall here, since i've found customers say their IT will not allow work email to forward to an external address. Some companies DO allow this though, and is BEST for you. You can run your Outlook program and setup a hard forward (or rule) from your work pc's Outlook, but most of this time you will need to leave your outlook running to receive the email on your BB.
I know this thread looks old, but I needed to put my 2 cents in, since i run through this multiple times on a day-to-day basis. Hope this helps anyone!