changing passwords in the prefs page.
It is enabled by default, but can be turned off if you want to only use
-some other form of authentication, such as [[openid]].
+some other form of authentication, such as [[httpauth]] or [[openid]].
+
+When the `account_creation_password` configuration option is enabled with
+a pass-phrase, this plugin prompts for the password when creating an
+account as a implistic anti-spam measure.
+(Some wikis edited by a particular group use an account creation password
+as an "ask an existing member to get an account" system.)
+
+