[CFT] Update OpenJDK6 to b21

[Jung-uk Kim]

I have updated ports/java/openjdk6 to b21 and it's available from 
here:

http://people.freebsd.org/~jkim/ports-openjdk6-b21.tar.bz2

Please test if you can.  Note files/patch-nio-kqueue is integrated 
with patch-set now, so you have to remove it if you want to extract 
the tarball directly on existing openjdk6 directory.

If there is no serious regression, I am going to commit it in a week 
or so.

Thanks!

Jung-uk Kim