Seems a good place to start understanding the code is the design fundamentals doc: http://code.google.com/p/jaikuengine/source/browse/trunk/doc...

The images they refer to are all in the /doc/ folder

For the curious, it's a reST document (http://docs.python.org/documenting/rest.html) so were you to check out the source via SVN (http://code.google.com/p/jaikuengine/source/checkout) you could use some tools to convert it to a more readable format (if you have docutils installed it probably came with some variation on rst2html or rst2pdf).

Though, looking at the Makefile it looks like you could also just run 'make api_docs'

Looking for XMPP related code on GAE.

svn checkout 15.23 MBytes transferred in 4 minute(s) and 29 second(s)

==================update==================

here we go:

http://jaikuengine.googlecode.com/svn/trunk/common/protocol/...

from common.protocol import xmpp

from common.protocol import sms

Now I am worried about XMPP and SMS abuse.