[ngIRCd-ML] Configuring Channel Key with Persistent Channels

All - I am trying to configure persistent channels with keys, but can't seem to figure out the proper syntax in the Modes section of the ngircd.conf. I have tried adding mode k followed by the password, and while the channel shows +k, anybody is able to join it without a key. What is the proper way to set this up? Thanks in advance, Adam