soft-knobs are always just representative for other knobs, that do have CC.
so when you automate that CC: you automate the parameter that is assigned to the soft-knob.
(as you wrote) VirusControl supports automation soft-knobs (but only via VST automation).
it's for TI Desktop, but should be the same, i think:
http://www.infekted.org/virus/showthread.php?t=29718