XML 1.1 - Problem? (Score 5, Informative)

A newline character should have no impact on with respect to backwards compatibility. The only negative impact with regards to a newline character should be contained to poorly written DOM code that parses out all nodes instead of just relavent nodes. Similar issue with SAX. Even if there were a backwards compatibility issue with a new XML spec, most people define their version number in their documents so the parser knows which spec to follow while parsing it.