In Clojure 1.6, we plan to move to JDK 1.6 as the minimum JDK.
This patch changes the build configurations for both Maven and Ant to assume JDK 1.6 as the "source" and "target" runtimes.
Configuration changes will be necessary on Hudson. We already build Clojure and contrib libraries on JDK 1.6 by default, but we will need to remove matrix test builds for JDK 1.5. See for example clojure-test-matrix and data.csv-test-matrix – coordinate with Stuart Sierra for this change.