diff --git a/mail/bsfilter/Makefile b/mail/bsfilter/Makefile
index d121abe3483e..a9d48f987694 100644
--- a/mail/bsfilter/Makefile
+++ b/mail/bsfilter/Makefile
@@ -1,33 +1,39 @@
 # Created by: Masafumi Otsune <info@otsune.com>
 
 PORTNAME=	bsfilter
 PORTVERSION=	1.0.19
 PORTREVISION=	3
 CATEGORIES=	mail ruby
 MASTER_SITES=	OSDN/bsfilter
 
 MAINTAINER=	ports@FreeBSD.org
 COMMENT=	Bayesian spam filter written in Ruby
 
 LICENSE=	GPLv2
 
 RUN_DEPENDS=	rubygem-gdbm>=2.0.0,2:databases/rubygem-gdbm
 
 NO_BUILD=	yes
 USE_RUBY=	yes
 USES=		shebangfix tar:tgz
 SHEBANG_FILES=	bsfilter/bsfilter
 
 OPTIONS_DEFINE=	EXAMPLES
 
+.include <bsd.port.pre.mk>
+
+.if ${RUBY_VER:M3*} != ""
+RUN_DEPENDS+=	rubygem-sdbm>=1.0.0:databases/rubygem-sdbm
+.endif
+
 do-install:
 	${INSTALL_SCRIPT} ${WRKSRC}/bsfilter/${PORTNAME} ${STAGEDIR}${PREFIX}/bin/${PORTNAME}
 	@${MKDIR} ${STAGEDIR}${EXAMPLESDIR}
 .for FILE in bsfilter.conf.sample dot-qmail.sample
 	${INSTALL_DATA} ${FILESDIR}/${FILE} ${STAGEDIR}${EXAMPLESDIR}
 .endfor
 .for DIR in mda mua
 	cd ${WRKSRC} && ${COPYTREE_SHARE} ${DIR} ${STAGEDIR}${EXAMPLESDIR}
 .endfor
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>