Blackberry BESX (BES Express) activation - BES service on BIS contract via activating by connecting to server?

Hi,

Looking for other opinions on this circumstance. A new client recently rolled out a BES express 5  installation despite only having 1 blackberry user.
Their network provider was Orange in the UK. All seemed well although there was some calendar synchronisation issues (Appointments entered on device did not go to server) which they asked me to investigate.

My investigation revealed that the account for the device was only a BIS account and I stopped my investigation there as I said BIS does to support full synchronisation like a BES or BESX does and they needed to change.

Orange provided contradicting information on tariffs and the client is annoyed as they were essentially sold blackberry without Orange explaining the BES aspect.
However Orange support have said that they can get round everything if they activate their Blackberry device by  connecting with USB to the BESX server and then do the enterprise activation.

So even though the particular handset is on a BIS tariff, support are saying they will receive BESX service (full synchronisation of everything) if they activate connecting handset to server.

I would have thought this was rubbish, but this is coming from Orange support.

Any opinions?

Note server is Windows SBS 2008.