I needed a client to access work's Cisco VPN client. Apparently, the official client from Cisco (version 4.8 or later) can be built to run on Dapper Drake. However, there is an open source alternative vpnc, for which there is an apt package.
I installed the vpnc package and it ran (sudo) without any problems. As an added bonus (unlike the official client) vpnc doesn't disable LAN traffic, is not a kernel module and doesn't require recompilation with each kernel upgrade.