"Two years after Java was delivered under the GPL we saw the first
release of the Sun-led OpenJDK project for a Java Development Kit built
using free and open-source code; that spawned the IcedT project lead by
Red Hat, to build an even freer OpenJDK - the OpenJDK had contained a
class-path exception to exempt from the GPL certain portions of the code
that Sun or others still owned and open sourcers couldn't touch. A
version of IcedTea shipped with Fedora in 2008 that was compatible with
Sun's official spec"