You can get the latest working versions via Anonymous CVS. If you are unfamiliar with CVS, see the O'Reilly Book Essential CVS, or CVS, or OpenCVS, an alternate implementation.
You need to download one CVS Module, called pageunit. There is one other module called pageunitweb, which is only of interest if you want to contribute improvements to the web site.
Almost all development of PageUnit is done using the Eclipse IDE. If you are using Eclipse, you can easily get pageunit from the CVS repository window (the CVS Module for pageunit is an Eclipse Java project). Check out the Head branch of each (the only branch that exists).
For command-line CVS, use :pserver:anoncvs@cvs.darwinsys.com:/cvspublic as your CVSROOT, e.g.,
Or put the corresponding values into e.g., the Eclipse CVS Repositories->New Repository dialog.
If you are not running Eclipse, you will need to modify build.xml for your use (this file is not necessarily up to date; look at the Jar files in the lib directory to see what your classpath should be set to).
Sending Updates: We're always glad to get corrections or improvements to the code, but please use cvs diff -u or Eclipse Team->Generate Patch. Thank you in advance for understanding that we don't have time to decode other formats, unless your correction is either really trivial or really important :-).