When trying to build icedtea-7.2.5.3 with only automake-15 installed, it dies with the error: /var/tmp/portage/dev-java/icedtea-7.2.5.3/work/icedtea-2.5.3/missing: line 81: automake-1.14: command not found I suppose that the make system has maintainer-mode enabled which has automake-1.14 hardcoded. Probably, it is possible to avoid the maintainer-mode or to use "eautoreconf" to avoid the artificial dependency; I have currently no time to try.
Version 7.2.5.3 is gone. Closing.