The jikes use flag has been deprecated since the introduction of the 
generation 2 Java setup ages ago. I just removed the last generation 1 
ebuilds using the use flag so I was also able to remove the jikes use 
flag from use.desc. For those who don't know the Java setup, jikes can 
still be used via
/etc/java-config-2/build/compilers.conf but it's disabled in quite a few 
ebuilds because of build failures.

Regards,
Petteri
--
Gentoo/Java project lead