Speedtouch 585 + UK Tiscali TV + Nortel Contivity vpn client

i am about to move home and was planning to take the opportunity to change to Tiscali TV, here in the UK.

But for my work i need the Nortel Contivity VPN client, v4.something

Since the Tiscali TV service seems to require the Speedtouch 585 my question is

will the Nortel Contivity VPN client support the st585?

thanks!