Command - /ChanServ SET VOICEGUARD
Usage   - /ChanServ SET <#channel> VOICEGUARD [ON/OFF]
If the VOICEGUARD option is on, only users with VOP or higher access can be voiced (MODE +v) on the channel.
Note: You need CO-FOUNDER or higher access on the channel to use this command.
Example(s):
/ChanServ SET #kobi VOICEGUARD ON
/ChanServ SET #kobi VOICEGUARD OFF