diff --git a/app-shells/mksh/mksh-59c.ebuild b/app-shells/mksh/mksh-59c.ebuild
index b17abe57684b1..26aec2d8e3a98 100644
--- a/app-shells/mksh/mksh-59c.ebuild
+++ b/app-shells/mksh/mksh-59c.ebuild
@@ -13,7 +13,7 @@ if [[ ${PV} == *9999 ]] ; then
 	inherit cvs
 else
 	SRC_URI="https://www.mirbsd.org/MirOS/dist/mir/mksh/${PN}-R${PV}.tgz"
-	KEYWORDS="~alpha amd64 arm arm64 ~hppa ~ia64 ~loong ~m68k ~mips ppc ppc64 ~riscv sparc x86 ~amd64-linux ~x86-linux"
+	KEYWORDS="~alpha amd64 arm arm64 ~hppa ~ia64 ~loong ~m68k ~mips ppc ppc64 ~riscv ~s390 sparc x86 ~amd64-linux ~x86-linux"
 fi
 
 DESCRIPTION="MirBSD Korn Shell"