diff --git a/x11-toolkits/open-motif/Makefile b/x11-toolkits/open-motif/Makefile
index 5f308789a4ad..1a2eb5ed3029 100644
--- a/x11-toolkits/open-motif/Makefile
+++ b/x11-toolkits/open-motif/Makefile
@@ -25,6 +25,7 @@ USE_GMAKE=	yes
 GNU_CONFIGURE=	yes
 CONFIGURE_ENV=	CPPFLAGS="-DCSRG_BASED -DXUSE_MTSAFE_API -DXNO_MTSAFE_PWDAPI"
 INSTALLS_SHLIB=	yes
+MAKE_ENV=	LANG=C
 
 DEMOS_SRC=	${WRKSRC}/demos/programs