Taglib Documentation

Hi,
I was trying to tweak the user container box and want to know what the
<jahiaHtml:groupList> tag does and what are its attributes. I checked out
the taglib documentation pdf at http://www.jahia.net/jahia/page585.html but
it doesn't provide info on this. Where can I find documentation on all jahia
tags may be similar to the JSTL doc
http://java.sun.com/products/jsp/jstl/1.1/docs/tlddocs/index.html by sun.

If the documentation is not available, can someone please point me to the
java classes for these taglibs. In case, I want to tweak around these
classes and create my own custom taglib, how do I do that?

Thanks
Sanjay Goel
http://sanjaygoel.blogspot.com