Simple VPN Connection

Hello,

I have a very simple question. I have Blackberry curve 8900 through BIS on Vodafone D2 Germany, with a flat rate internet.

When I am in my company, there is an open-access Wireless Network, which you can log on without username and password, but in order to be able to browse the internet and access intranet webpages, you have to make a vpn connection first, which has an address like : vpn.domain.de, with username and password.

Can I somehow make this VPN Connection through my bb?

On my Vista computer, I use the Cisco Anyconnect VPN Client, but how do I set up my blackberry with VPN, so I can use the internet of this wifi?

Is this possible? Maybe not possible with BIS?