World IPv6 Day
By alexismp on Jun 07, 2011
IPv6 was first introduced in 2002 in Java 1.4 (almost a decade ago!) with no impact on the developer and support on all platforms by 1.4.2 in 2003.
Oracle GlassFish Server 2.1.1 and 3.1 are both IPv6 ready (see this compatibility matrix) and I would expect most Java software to be capable as well.