Index: Mk/Uses/metaport.mk
===================================================================
--- Mk/Uses/metaport.mk
+++ Mk/Uses/metaport.mk
@@ -8,6 +8,7 @@
 .if !defined(_INCLUDE_USES_METAPORT_MK)
 _INCLUDE_USES_METAPORT_MK=	yes
 
+LICENSE=	NA
 MASTER_SITES=	#
 DISTFILES=	#
 EXTRACT_ONLY=	#
Index: Mk/bsd.licenses.db.mk
===================================================================
--- Mk/bsd.licenses.db.mk
+++ Mk/bsd.licenses.db.mk
@@ -77,6 +77,9 @@
 # Others
 _LICENSE_LIST+= NONE
 
+# Non Applicable for metaports
+_LICENSE_LIST+= NA
+
 # List of groups (only names must be present)
 
 _LICENSE_NAME_FSF=	Free Software Foundation Approved
@@ -398,6 +401,10 @@
 _LICENSE_NAME_RUBY=	Ruby License
 _LICENSE_GROUPS_RUBY=	FSF
 
+_LICENSE_NAME_NA=	Non Applicable
+_LICENSE_GROUPS_NA=	#empty
+_LICENSE_PERMS_NA=	auto-accept
+
 _LICENSE_NAME_NONE=	No license specified
 _LICENSE_GROUPS_NONE=	# empty
 _LICENSE_PERMS_NONE=	none
Index: Mk/bsd.licenses.mk
===================================================================
--- Mk/bsd.licenses.mk
+++ Mk/bsd.licenses.mk
@@ -211,6 +211,11 @@
 # and negative) duplicated components.
 
 .    if ${_LICENSE_COMB} == "single"
+
+.      if ${LICENSE:MNA} && !defined(USES) || empty(${USES:Nmetaport})
+_LICENSE_ERROR?=	NA can only be used in metaports
+.      endif
+
 # Defaults to empty
 _LICENSE_GROUPS?=	#
 # Start
@@ -294,6 +299,10 @@
 
 .    else
 
+.      if ${LICENSE:MNA}
+_LICENSE_ERROR?=	NA can only be used in single licenses
+.      endif
+
 .      if defined(LICENSE_FILE)
 .        for lic in ${_LICENSE}
 LICENSE_FILE_${lic}?=	${LICENSE_FILE}