Index: Mk/Uses/perl5.mk
===================================================================
--- Mk/Uses/perl5.mk
+++ Mk/Uses/perl5.mk
@@ -42,13 +42,13 @@
 
 USE_PERL5?=	run build
 
+.include "${PORTSDIR}/Mk/bsd.default-versions.mk"
 .if exists(${LOCALBASE}/bin/perl5)
 .sinclude "${LOCALBASE}/etc/perl5_version"
 .if !defined(PERL_VERSION)
 PERL_VERSION!=	perl -e 'printf "%vd\n", $$^V;'
 .endif
 .else
-.include "${PORTSDIR}/Mk/bsd.default-versions.mk"
 .if ${PERL5_DEFAULT} == 5.16
 PERL_VERSION=	5.16.3
 .elif ${PERL5_DEFAULT} == 5.18
@@ -80,14 +80,23 @@
 
 PERL_ARCH?=	mach
 
-# there must always be a default to prevent dependency failures such
-# as "ports/lang: not found"
 .if   ${PERL_LEVEL} >= 502000
 PERL_PORT?=	perl5.20
+_MIN_PERL_VERSION=	5.20.1_10
+_MAX_PERL_VERSION=	5.22
 .elif ${PERL_LEVEL} >= 501800
 PERL_PORT?=	perl5.18
-.else # ${PERL_LEVEL} < 501800
+_MIN_PERL_VERSION=	5.18.1_11
+_MAX_PERL_VERSION=	5.20
+.elif ${PERL_LEVEL} >= 501600
 PERL_PORT?=	perl5.16
+_MIN_PERL_VERSION=	5.16.1_18
+_MAX_PERL_VERSION=	5.18
+.else
+IGNORE=	Unsupported perl5 version ${PERL_VERSION}
+# there must always be a default to prevent dependency failures such
+# as "ports/lang: not found"
+PERL_PORT?=	perl${PERL5_DEFAULT}
 .endif
 
 SITE_PERL_REL?=	lib/perl5/site_perl
@@ -208,20 +217,23 @@
 .endif # defined(BATCH) && !defined(IS_INTERACTIVE)
 .endif # configure
 
+_PERL_DEPENDS=	perl5>=${_MIN_PERL_VERSION}:${PORTSDIR}/lang/${PERL_PORT} \
+		perl5<${_MAX_PERL_VERSION}:${PORTSDIR}/lang/${PERL_PORT}
+
 .if ${_USE_PERL5:Mextract}
-EXTRACT_DEPENDS+=	${PERL5}:${PORTSDIR}/lang/${PERL_PORT}
+EXTRACT_DEPENDS+=	${_PERL_DEPENDS}
 .endif
 
 .if ${_USE_PERL5:Mpatch}
-PATCH_DEPENDS+=		${PERL5}:${PORTSDIR}/lang/${PERL_PORT}
+PATCH_DEPENDS+=		${_PERL_DEPENDS}
 .endif
 
 .if ${_USE_PERL5:Mbuild}
-BUILD_DEPENDS+=		${PERL5}:${PORTSDIR}/lang/${PERL_PORT}
+BUILD_DEPENDS+=		${_PERL_DEPENDS}
 .endif
 
 .if ${_USE_PERL5:Mrun}
-RUN_DEPENDS+=		${PERL5}:${PORTSDIR}/lang/${PERL_PORT}
+RUN_DEPENDS+=		${_PERL_DEPENDS}
 .endif
 
 .if ${_USE_PERL5:Mconfigure}
Index: lang/perl5.16/Makefile
===================================================================
--- lang/perl5.16/Makefile
+++ lang/perl5.16/Makefile
@@ -101,12 +101,16 @@
 # change PKGNAME to reflect this
 .if ${PERL_VER} == ${PERL5_DEFAULT}
 PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
-.else
+.elif defined(PACKAGE_BUILDING)
 # make PKGNAME unique among other lang/perl5.x
 PKGNAMESUFFIX=	${PERL_VER}
 # always add default perl5 pkgname to conflicts
 CONFLICTS_INSTALL+=	perl5-*
-.endif
+.else
+# If not building packages, keep PKGNAME=perl5 to help with upgrading
+PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
+CONFLICTS_INSTALL+=	perl5-5.{18,20}.*
+.endif # PACKAGE_BUILDING
 
 .if defined(PERL_VENDOR_PREFIX)
 CONFIGURE_ARGS+=	\
Index: lang/perl5.18/Makefile
===================================================================
--- lang/perl5.18/Makefile
+++ lang/perl5.18/Makefile
@@ -118,12 +118,16 @@
 # change PKGNAME to reflect this
 .if ${PERL_VER} == ${PERL5_DEFAULT}
 PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
-.else
+.elif defined(PACKAGE_BUILDING)
 # make PKGNAME unique among other lang/perl5.x
 PKGNAMESUFFIX=	${PERL_VER}
 # always add default perl5 pkgname to conflicts
 CONFLICTS_INSTALL+=	perl5-*
-.endif
+.else
+# If not building packages, keep PKGNAME=perl5 to help with upgrading
+PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
+CONFLICTS_INSTALL+=	perl5-5.{16,20}.*
+.endif # PACKAGE_BUILDING
 
 .if defined(PERL_VENDOR_PREFIX)
 CONFIGURE_ARGS+=	\
Index: lang/perl5.20/Makefile
===================================================================
--- lang/perl5.20/Makefile
+++ lang/perl5.20/Makefile
@@ -122,12 +122,16 @@
 # change PKGNAME to reflect this
 .if ${PERL_VER} == ${PERL5_DEFAULT}
 PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
-.else
+.elif defined(PACKAGE_BUILDING)
 # make PKGNAME unique among other lang/perl5.x
 PKGNAMESUFFIX=	${PERL_VER}
 # always add default perl5 pkgname to conflicts
 CONFLICTS_INSTALL+=	perl5-*
-.endif
+.else
+# If not building packages, keep PKGNAME=perl5 to help with upgrading
+PKGNAMESUFFIX=	${PERL_VERSION:C/\.[0-9]+\.[0-9]+$//}
+CONFLICTS_INSTALL+=	perl5-5.1{6,8}.*
+.endif # PACKAGE_BUILDING
 
 .if defined(PERL_VENDOR_PREFIX)
 CONFIGURE_ARGS+=	\