This command allows you to set the password for a room, without using the room in question and without being identified to it.
Example:
/msg chanserv setpass #webchat webPass
This is useful for similar reasons as ftransfer. Often you may want to make sure a particular person has the password for the room, but if you are not certain that they set the last password, you should not tell them what it was. Since many people reuse passwords, being given a password used on a chat network may allow you to access other things for which they need a password. While recycling passwords is not a safe thing to do, it is good to help prevent people from being hurt by their own mistakes.