I've just installed Fedora 14 with KDE and I have created VPN entries in Network Manager but how do I activate any of those entries ? My vpn server is CISCO2911/K9 I have tried everything I could think of but so far no success. I have all the plugins installed and I have no problems of creating VPN connection from GNOME but not from KDE.

Assuming you have successfully created the VPN connections, all you should need to do to open them is to click on the network management applet in the system tray and select the VPN connection(s) you wish to connect to. This should cause them to connect (or provide some feedback on why the connection failed).