Does CKEditor support ...?

You will not able to do that with FCKeditor directly. This is something related to diff and text comparison systems, which should be done in the server side. We don't have much control of it in the browser.

It is not that easy Marcus. Typing is just one of the ways to add/delete content. You can also drag and drop and cut and paste, which make things much harder for us.

EditLive is a Java application. They have much more control over the editor because of it, because they don't use the browser for editing. Also, they don't need to take care about things like code size and performance issues, like we have to have in JavaScript. The drawback is that you need Java and all that stuff to run it.

I think we'll not be able to support such feature any time soon. And I don't expect having other JavaScript based editor to do so that early.

I still insist, any versioning effort should be done as a dedicated tool in your system, processed at the server side. This is the way most of the Wikis out there do it, for example, and it proved to be a good solution for it.