topiclock - users with the topic access can change the topic using /topic and ChanServ will change the topic back to what it was for users with no access
Atheme topiclock
-ChanServ- ***** ChanServ Help *****
-ChanServ- Help for SET TOPICLOCK:
-ChanServ-
-ChanServ- SET TOPICLOCK causes ChanServ to revert
-ChanServ- topic changes by users without the +t flag.
-ChanServ- Topic changes during netsplits or services
-ChanServ- outages will always be reverted.
-ChanServ-
-ChanServ- TOPICLOCK requires KEEPTOPIC and will
-ChanServ- automatically enable it; disabling KEEPTOPIC
-ChanServ- will disable TOPICLOCK also.
-ChanServ-
-ChanServ- Syntax: SET <#channel> TOPICLOCK ON|OFF
-ChanServ-
-ChanServ- Example:
-ChanServ- /msg ChanServ SET #foo TOPICLOCK ON
-ChanServ- ***** End of Help *****