diff --git a/app-text/calibre/calibre-4.10.1-r2.ebuild b/app-text/calibre/calibre-4.10.1-r2.ebuild
index 2004b89741dd2..ff49270f89162 100644
--- a/app-text/calibre/calibre-4.10.1-r2.ebuild
+++ b/app-text/calibre/calibre-4.10.1-r2.ebuild
@@ -184,7 +184,7 @@ src_install() {
 	#    raise ValueError, 'unknown locale: %s' % localename
 	#ValueError: unknown locale: 46
 	export -n LANG LANGUAGE ${!LC_*}
-	export LC_ALL=C #684484
+	export LC_ALL=C.utf8 #709682
 
 	# Bug #295672 - Avoid sandbox violation in ~/.config by forcing
 	# variables to point to our fake temporary $HOME.
diff --git a/app-text/calibre/calibre-4.9.1-r2.ebuild b/app-text/calibre/calibre-4.9.1-r2.ebuild
index 02806f489cdbf..9a06547f837d5 100644
--- a/app-text/calibre/calibre-4.9.1-r2.ebuild
+++ b/app-text/calibre/calibre-4.9.1-r2.ebuild
@@ -184,7 +184,7 @@ src_install() {
 	#    raise ValueError, 'unknown locale: %s' % localename
 	#ValueError: unknown locale: 46
 	export -n LANG LANGUAGE ${!LC_*}
-	export LC_ALL=C #684484
+	export LC_ALL=C.utf8 #709682
 
 	# Bug #295672 - Avoid sandbox violation in ~/.config by forcing
 	# variables to point to our fake temporary $HOME.