diff --git a/lang/moscow_ml/Makefile b/lang/moscow_ml/Makefile
index b2a1111113a0..8fbbeb53f99d 100644
--- a/lang/moscow_ml/Makefile
+++ b/lang/moscow_ml/Makefile
@@ -20,6 +20,7 @@ MOSMLHOME=	$(PREFIX)/moscow_ml
 ALL_TARGET=	world MOSMLHOME=$(MOSMLHOME)
 INSTALL_TARGET=	install MOSMLHOME=$(MOSMLHOME)
 WRKSRC=		${WRKDIR}/mosml/src
+USE_PERL5=	yes
 
 post-install:
 	${SED} -e 's|^MOSMLHOME=.*|MOSMLHOME=${MOSMLHOME}|' \