I have a client who want to add a blackberry to their new SBS 2003 server.
I have read all the posts and have installed a copy of BES 4.1.4 that was free for the first device on the server. This all work s with a SQL 2005 service how ever i am not able to get a device the pair it just sits there activating.

I then have discovered that the blackberry in setup on personal orange UK account with basic blackberry service and needs to be in a business connection with black berry BES service costing £35 per month!!

So if i add another user it will cost £300 to add five user + pay orange £35 per month!!!

Is this correct??

If so that seems a waste of money to me when you could have a windows mobile PDA phone on a fixed data plan and active sync direct to the exchange server at a cost of £6pm on orange.

Yes, that sounds correct.
Each device needs it's own BES CAL and also needs it's own enterprise BlackBerry Data Plan.

Guessing this is Exchange as a mail system but if i may be permitted to give my 2p.

We are a Domino shop and have been looking to roll out mobile email and to start with we tried the Commntime solution, mNotes. It worked perfectly but we had issues with data charges when out of the UK and as it was rolled out on trial to three managers who travel fairly extensively the bills for the trial period were quite high. The data charges for roaming users are unpleasant.

We then got three BBs in to test and our carrier has quoted an acceptable monthly figure which is valid for unlimited BB traffic world wide.

Suffice it to say that so far the test has gone easily and despite my best efforts at not being impressed i have been impressed. The BBs are working and globe trotting with ease. And the speed with which mail is delivered to the BB is not a lot short of amazing.

Unfortunately, that is the way it works. You have to have a BB data plan on the bb to get it to connect to the wireless infrastructure.

Why is this unfortunate?

Remember - "you get what you pay for". Before getting a bb, I used to be quite the proponent for Windows Mobile. But once you've set up and used a few bb's you'll be hooked.

What would you guys say are the advantages of blackberry over MS WM6 PDAs?

There's not enough time in a day to answer this question.

Honestly, no one can answer this for you.
You need to do your own due diligence on each system to determine the needs of your environment.
Maybe WM will end up being the right choice for you.
Neither system is better than the other. Your needs will determine the path you should take.