Help on filters!

[Emmanuel <e allaud wanadoo fr>]

	Hi all,
I'm trying to code the filter_run* functions, but I'm confused on how to 
make the actual filtering : eg how I access the message body to do the 
match, how I apply the regexs, how to use the libmutt facilities...
I would like someone to point me to docs or give me some guidelines to 
help me progress faster.
Thanks
Manu