Today I tried JSPWiki 2.4, it is much improved version, here is a brief of some of the new security features:

• Wiki-level and page-level privilege control.
• Security can be applied to individual users as well as to entire groups.
• Authentication: simple XML file-based, database-based, container-managed and custom authentication modules can be used.
• Authorization: security policies and ACLs can be applied to authentication status (anonymous, cookie-based, authenticated), container roles or ad hoc wiki groups you set up yourself

Also, the editor is improved and have the option to use a GUI editor that is based on Java, my FireFox 2.0 worked with it without problems.

It is extremely easy to install, you just drop the war file in the JSP server webapps directory. JSPWiki by default uses no database, it stores all pages and attachments in the file system, you can install a pluging to use MySQL dbase.

I used it for more than 2 year and it was very reliable and helpful, so I encourage everyone to use it. You can use it as a personal knowledge base or as a department knowledge base.