SMods/Admins can warn via profile, and mods of a forum can warn people in those forums (if they have made posts).
@ jluerken - I'm afraid it doesn't use a hierachical system, but you can insert protected usergroups, i usually enter all usergroup IDs which are mods/s.mods/admins, that way only staff can warn members.
@ hydrostatic - I'll get that in for v1.1
@ kall - Sorry, i'll make sure that's fixed in v1.1, nothings perfect, right?
- Zero Tolerance