diff --git a/bin/tests/system/conf.sh.common b/bin/tests/system/conf.sh.common
index 2d1c8a83ab..c491a6926e 100644
--- a/bin/tests/system/conf.sh.common
+++ b/bin/tests/system/conf.sh.common
@@ -20,7 +20,7 @@ testsock6() {
 	fi
 }
 
-export LANG=C
+export LC_ALL=C
 
 
 #