--- acpica-unix/compiler/Makefile
+++ acpica-unix/compiler/Makefile
@@ -97,7 +97,7 @@
 #YACC=	yacc
 YACC=	bison
 YFLAGS+= -v -d
-LEX=	flex
+LEX=	LC_ALL=C flex
 LFLAGS+= -i
 
 #.if $(YACC) == "bison"