sys-app/portage/ version 2.1_pre9-r4 In make.conf.example it includes this line (from cnf/make.conf) #PORTAGE_ELOG_MAILSUBJECT="package ${PACKAGE} merged on ${HOST} with notice" Simply uncommenting this line does not work because the $ need escaping with \ as is done in make.globals otherwise you end up with subjects such as "package merged on with notice". Either this line should include \$ or there should be a note to that effect in the description beforehand where it explains about the ${PACKAGE} and ${HOST} keywords.
fixed in rev 3248.
Released in 2.1_pre10.