Vista - VPN Session Icon Disappears, so I can't close Session

I connect to my network at work using Juniper's Network Connect 5.5.0 via a
Linksys wireless router. When I am connected to my work location it puts an
icon in system tray. If I want to disconnect I click on icon and sign out.
However, sometimes after a few minutes the icon in the system tray
disappears, so I can't close the session. I am still connected because I can
use the network drive and my email which is connected to the server at work.
I checked the icon in the tray that shows network connnections. It shows two
connections. ONe is the wireless router and the other is an unidentified
public network. I go to Network and sharing and I see both network
connections. THere is a button to disconnect the wireless connection, but no
disconnect button for the unidentified public connection which I am assuming
is VPN connection. I guess I can just shut down the computer, but that leaves
my session open on the host computer. I'm sure it will eventually be
terminated, but not a good way to do things. Any suggestions are appreciated.