diff --git a/databases/ruby-bdb/Makefile b/databases/ruby-bdb/Makefile
index 98ea38455a98..09022fb8704b 100644
--- a/databases/ruby-bdb/Makefile
+++ b/databases/ruby-bdb/Makefile
@@ -26,6 +26,9 @@ INSTALL_TARGET=	site-install
 
 DOCS=		Changes README.en bdb.html bdb.rd docs/*
 
+post-patch:
+	${RUBY} -i -pe 'sub /have_library\("db"/, %q:have_library("db3":' ${WRKSRC}/src/extconf.rb
+
 post-install:
 .if !defined(NOPORTDOCS)
 	${MKDIR} ${RUBY_EXAMPLESDIR}/${PORTNAME}/