groovy/groovy-core — pull request #219 by jwagenleitner (2013-07-20 22:42:02+00:00)
Title: Document limitation of normal map-style constructor use when using the Immutable annotation

See http://groovy.329449.n5.nabble.com/Unexpected-behaviour-when-using-Immutable-on-a-class-with-java-util-Map-field-tp5716170.html