. Note that the time zone data is in the public domain (according to

ftp://ftp.iana.org/tz/tz-link.html).  Specifically the sentence

  "The public-domain time zone database contains code and data that
  represent the history of local time for many representative locations
  around the globe."

java/java-zoneinfo/Makefile

@@ -11,6 +11,8 @@ DISTNAME=	javazi-${DISTVERSION}
 MAINTAINER=	glewis@FreeBSD.org
 COMMENT=	Updated Java timezone definitions
 
+LICENSE=	PD
+
 WRKSRC=		${WRKDIR}
 NO_BUILD=	yes