diff --git a/src/test/Makefile b/src/test/Makefile
index c7b343a4a376d16d633f09ec76692aa684416768..12b6cf1049af703a54299eea11b719dd6f607e41 100644
--- a/src/test/Makefile
+++ b/src/test/Makefile
@@ -5,13 +5,13 @@ LC2=../lus2lic --compile-all-items
 NL="----------------------------------------------------------------------\\n"
 filter_line=grep -v Opening\ file
 
-OK_LUS=$(shell find should_work -name "*.lus" -print | sort -n)
+OK_LUS=$(shell find should_work -name "*.lus" -print | LC_ALL=C sort -n)
 
-KO_LUS=$(shell find should_fail -name "*.lus" -print | sort -n)
+KO_LUS=$(shell find should_fail -name "*.lus" -print | LC_ALL=C sort -n)
 
 ALL_LUS=$(OK_LUS) $(KO_LUS)
 
-LIC=$(shell find should_work -name "*.lic" -print | sort -n)
+LIC=$(shell find should_work -name "*.lic" -print | LC_ALL=C sort -n)
 
 
 when: