CMS for software documentation

Hello,

Right now I am looking for a cms, or something similar, where I can write down the documentation of my projects.

I already looked at projects like "tikiwiki", "redmine", "mediawiki" and some more.

What I am looking for is a wiki like site with a WYSWYIG editor and an editable navigation so I can structure hierarchies like:

project
- install
- - web service
- changelog
- user
- - design mode
- - - drag mode

Plus point would be inline edit like in tiki wiki. I have to say, that I really like tiki wiki, but I don't get the navigation thing. I already tried structures and tocs etc, but i want it simple and easy.

Does someone know of any such tool? Or, what tools do you use for your documentation? (I am not talking about automatic documentation tools!)