acpid-2.0.9 was released lately. Seems like a good idea to have it bumped.
Sorry didn't know there was this bug. *acpid-2.0.10 (21 May 2011) 21 May 2011; Samuli Suominen <ssuominen@gentoo.org> +acpid-2.0.10.ebuild: Version bump. *acpid-2.0.9 (25 Apr 2011) 25 Apr 2011; Samuli Suominen <ssuominen@gentoo.org> +acpid-2.0.9.ebuild: Version bump. Just for the record, 2.0.10 is the first version that works properly with systemd per upstream ChangeLog.