The new gcj package with version 5 libraries and compiler has been
available in rawhide for a couple of weeks now.
This package is available from the yum development repo as
gcc-java.*.4.1.2-3.
If you are a maintainer of a package that has a dependency on libgcj
please make sure that your package builds. I don't expect there to be
many problems, but it's worth checking.
Thanks,
Andrew.