Intentionally I didn't add (the "big") perl extension to the deps because it's more (if at all) a soft dep... you can always create the needed .conf from a cisco .pcf without using the perl script by hand (it's ascii stuff), you just need to decrypt the group password, which you can do by googling for a web version of the script
and tiny vpnc itself doesn't need perl at all...
Maybe this can be turned into a real clean soft dep if tc has got the feature some day