R help - Jul 2012 - customize packages' help index ( 00index.html file )

Hi all,

I'm writing my packages helps files and I'm not really satisfied by the 
visual results.

I'm would like to make subsections in a package "function help
index" file.

I would like for example to put all S4 object documentation link 
together, then all the getters function.. and so on..

Does someone know if it's possible to do it?
Is it possible to define by myself the html/00index.html file that will 
be use in my package?

If it's not possible, how could I add the alphabetic subsections that 
exist in most of packages index help files?

Best,

Damien