I have it running under Gentoo. I haven't tried using dig certificates yet but it does work. You have to manually define a profile file in /etc/CiscoSystemsVPNClient/Profiles and then make sure that you've run vpnclient_init that should me located in your /etc/rc/init.d directory (I think that is it for RH. For Gentoo it is different). After that you can do a vpnclient connect xxxx.pcf.