diff --git a/japanese/makejvf/Makefile b/japanese/makejvf/Makefile
index 98abb3486c2c..052783dcbb1c 100644
--- a/japanese/makejvf/Makefile
+++ b/japanese/makejvf/Makefile
@@ -18,6 +18,9 @@ DOCS=		README.1st README.txt \
 		test1.tex test2.tex kuten2jis jy1mch.fd
 
 NO_STAGE=	yes
+
+MAKE_JOBS_UNSAFE=	yes
+
 post-install:
 .if !defined(NOPORTDOCS)
 	${MKDIR} ${DOCSDIR}
diff --git a/mail/vm/Makefile b/mail/vm/Makefile
index 8af5d5608544..0aec25de9576 100644
--- a/mail/vm/Makefile
+++ b/mail/vm/Makefile
@@ -9,8 +9,8 @@ MASTER_SITES=	https://launchpad.net/${PORTNAME}/8.1.x/${PORTVERSION}/+download/
 PKGNAMESUFFIX=	-${EMACS_PORT_NAME}
 EXTRACT_SUFX=	.tgz
 
-MAINTAINER= ports@FreeBSD.org
-COMMENT=	A mail reader running inside Emacs or XEmacs
+MAINTAINER=	ports@FreeBSD.org
+COMMENT=	Mail reader running inside Emacs or XEmacs
 
 GNU_CONFIGURE=	yes
 USE_EMACS=	yes
@@ -23,4 +23,7 @@ MAKE_ARGS=	prefix=${PREFIX} \
 INFO=		vm vm-pcrisis
 
 NO_STAGE=	yes
+
+MAKE_JOBS_UNSAFE=	yes
+
 .include <bsd.port.mk>
diff --git a/sysutils/boxbackup-devel/Makefile b/sysutils/boxbackup-devel/Makefile
index 192343b1ba9e..c52899ad8e3d 100644
--- a/sysutils/boxbackup-devel/Makefile
+++ b/sysutils/boxbackup-devel/Makefile
@@ -42,6 +42,9 @@ SERVER_DESC=		Install the bbstored server
 GNUREADLINE_DESC=	Enable the use of GNU readline
 
 NO_STAGE=	yes
+
+MAKE_JOBS_UNSAFE=	yes
+
 .include <bsd.port.options.mk>
 
 .if ${PORT_OPTIONS:MGNUREADLINE}
diff --git a/textproc/ats-contrib-parcomb/Makefile b/textproc/ats-contrib-parcomb/Makefile
index 71100c2b3756..cb31bacf5aea 100644
--- a/textproc/ats-contrib-parcomb/Makefile
+++ b/textproc/ats-contrib-parcomb/Makefile
@@ -13,5 +13,8 @@ COMMENT=	Parser combinators for ATS language
 ATS_CTRB=	parcomb
 
 NO_STAGE=	yes
+
+MAKE_JOBS_UNSAFE=	yes
+
 .include "${.CURDIR}/../../lang/ats/bsd.ats.mk"
 .include <bsd.port.mk>
diff --git a/textproc/exmpp/Makefile b/textproc/exmpp/Makefile
index ced0a6bd2821..97f4e8e24007 100644
--- a/textproc/exmpp/Makefile
+++ b/textproc/exmpp/Makefile
@@ -38,6 +38,9 @@ CONFIGURE_ARGS+=	--enable-documentation
 .endif
 
 NO_STAGE=	yes
+
+MAKE_JOBS_UNSAFE=	yes
+
 pre-configure:
 	@cd ${WRKSRC} && ${AUTORECONF} -ivf