The Juniper "Network Connect" VPN client (with cache cleaner) works just fine under Windows - I'm in the process of rolling this same product out where I work. However, it will only give you VPN access to the *windows virtual machine* running under Paralells, not anything running natively on the Macintosh.
There's a native Macintosh NC client, but the IT person at your office will have to create a separate "profile" for the Macintosh client (that doesn't use the cache cleaner) for it to work properly.
The Parallels/Windows XP solution will work just fine. It's how I test the Windows client at home.
Last edited: May 22, 2007