After breaking Cisco's vpnclient AGAIN by upgrading to Fedora Core 6, and starting to go through the headache of trying to get it to compile, I poked around a bit to look for alternatives. Voila! I found vpnc, installed it, and had it up and running in no time.
Of course I'm just using the default configuration for now until I have time to try out some advanced configuration and scripting, and maybe the GUI.
Anyhow, good riddance to the terrible Cisco client for Linux.