Earlier quoted context omitted.
It is commentary though, not imitation. You are allowed to comment on things by name. If Shell, for instance sued shelloutsounds.org for the domain, I do not think they would have much of a case and the same applies here. If fixubuntu is using the word 'ubuntu' to mean the company Ubuntu, then the other word is obviously 'fix' and you would be hard pressed to argue that it isn't simply a critical statement rather tha…
They say they are happy to have the commentary, but their policy states that you cannot use ubuntu in a domain name or the ubuntu logo without permission. This applies to everyone.
moocowduckquack is explaining that the law already gives rights and obligations wrt trademark use.
It's helpful to know the difference between public law and contracts; they have the same effects (creating rights and obligations), but public law applies to everyone (within a jurisdiction) and contracts don't.