Instruction for the installation of Cisco VPN client on Debian based GNU/Linux
(32/64 bit OS)

Download the file  vpnclient-linux-x86_64-4.8.02.0030-k9.tar.gz from http://projects.tuxx-home.at/ciscovpn/clients/linux/4.8.02/
Download the 4.8.02-64bit.patch for the 64bit OS: http://birdman.dynalias.org/CiscoVPN/4.8.02-64bit.patch

Create a temporary folder vpn: mkdir vpn
Put the downloaded files into this folder: mv vpnclient-linux-x86_64-4.8.02.0030-k9.tar.gz vpn
                                           mv 4.8.02-64bit.patc vpn
Go into the vpn folder: cd vpn
Untar the client:   tar -xzf vpnclient-linux-x86_64-4.8.02.0030-k9.tar.gz
the client objects and source files are contained in the vpnclient folder
copy the patch in the vpnclient folder in case of 64 bit OS: cp 4.8.02-64bit.patch vpnclient

Go into the vpnclient folder: cd vpnclient
Apply the patch: path -p1 < 4.8.02-64bit.patch

Install the vpnclient: sudo ./vpn_install

Tested on Ubuntu 8.10 kernel  2.6.27-9-generic #1 SMP Thu Nov 20 22:15:32 UTC 2008 x86_64 GNU/Linux

ps
And don't forget to install the library 32bit for 64bit machine based (it's a little but astonishing the CISCO vpn client is half 64bit and half 32, "mah? disse il coniglio")

francesco