I've put updated version 1.3.1 up for download. This version fixes a documentation error and some behavior in the auth() function. There was a previously undocumented feature that I've now taken advantage of. There were also two functions recently depreciated from the API that I've removed implementation of.
The biggest change is that I've included all of the PEAR prerequisites so that you shouldn't have to do any setup of PEAR to get this running. If you've already got the packages installed, it will prefer to use those instead of the ones I've included. For the Database support, I've only included MySQL and Postgres. You can download and install others from http://pear.php.net/ if you need another type of database.