a cms on top of jackrabbit and extending jackrabbit

[Reza Ghaffaripour]

Hi,

I am new to the concept of CMS and Jackrabbit. I was planning to create
an open source and specialized CMS for my offline media. I also decided
to be as much as possible in-dependent of the JSR and jackrabbit
interfaces and classes because they are almost new and change a lot. I
just wanted to know the best practices of using JSR/ Jackrabbit? Should
I extend Jackrabbit or just use it with some proxies/ associations? What
should be the degree of dependency to the JSR 170? 

Thanks