Stock Answer: Tainted Kernel

Q: I started the vpnclient, and I received this error message:

Warning: Module cisco_ipsec will taint the kernel: non-GPL license - Proprietary
See http://www.tux.org/lkml/#export-tainted for information about tainted modules

A: This is normal behavior. The kernel developers wish to inform users when a module uses a license that is not compatible with the GNU General Public License. In this case, the Cisco VPN module uses a 'Proprietary' license. The kernel is only "tainted" in the moral and ethical sense - it remains fully functional.