On June 21, 2010 thesource bundle for OpenJDK 6 b20 was published.

The predominant change in this build was rebranding, replacing Sun copyrights with Oracle ones. In the HotSpot repository, this was largely accomplished by Andrew John Hughes's backport of HotSpot 17 into OpenJDK 6. Additional fixes for Zero were also applied as were backports of Nimbus and timezone changes.On the build front, the jaxp and jax-ws source bundles are not downloaded by default anymore. To allow them to be downloaded, add "ALLOW_DOWNLOADS=true" to the top-level make command.

A detailed list of all the changes is also available.

Read More about [OpenJDK 6: b20 Source Bundle Published...