diff --git a/lang/asn1c/Makefile b/lang/asn1c/Makefile
index 83c4567ff23b..61f1b58543b6 100644
--- a/lang/asn1c/Makefile
+++ b/lang/asn1c/Makefile
@@ -17,6 +17,7 @@ COMMENT=	Modern ASN.1 to C compiler
 
 GNU_CONFIGURE=	yes
 CONFIGURE_TARGET=--build=${MACHINE_ARCH}-portbld-freebsd${OSREL}
+USE_PERL5=	yes
 
 MAN1=	asn1c.1 enber.1 unber.1