I am looking for a small wiki engine that is easy to embed into an existing PHP application. Or perhaps a set of libraries to handle all the typical wiki functions.
Currently I am using ErfurtWiki, but it is starting to show its age. It hasn't been updated since 2005, and several of the pages on sourceforge appear to have been hacked.
I will be including it with a GPLv2 application so a GPL compatible license is important.
Edit:
To update, mostly I am just looking for text formatting/parser functionality. I want to deal with the storage, security, rev history, etc on my own.
Pear::Text_Wiki is another option, albeit it only handles the case of text formatting. It has not been updated since June of 2007, but includes several Wiki formats (all of which have other latest release dates).
The formats that Text_Wiki supports are:
It has an LGPL license, so there should be no licensing problems with including in a GPL project.