Hey I would like to order a good recommended Custom CMS book.
Hopefully that I can get on www.bol.com.

Mine languages are html,xhtml,css,javascript,php,sql and ajax.
I don't mind to add learning a new language.

I know that there are a tons of cms's but I want to take a look under the hood and create mine own engine just to know how all works and so that I can adapt the files on mine own.

If it requires a language that I don't know then I don't mind to learn that.

I hope on some good up-to-date recommendations.