Index: ruby21/Makefile
===================================================================
--- ruby21/Makefile	(revision 433785)
+++ ruby21/Makefile	(working copy)
@@ -56,7 +56,7 @@
 EDIT_DESC=		Which line editing lib to use
 LIBEDIT_DESC=		Use libedit
 READLINE_DESC=		Use libreadline
-CAPIDOCS_BUILD_DEPENDS=	doxygen>0:devel/doxygen \
+CAPIDOCS_BUILD_DEPENDS=	doxygen>1.8.12,2:devel/doxygen \
 			dot:graphics/graphviz
 CAPIDOCS_CONFIGURE_ENABLE=	install-capi
 GMP_CONFIGURE_WITH=	gmp
Index: ruby22/Makefile
===================================================================
--- ruby22/Makefile	(revision 433785)
+++ ruby22/Makefile	(working copy)
@@ -57,7 +57,7 @@
 EDIT_DESC=		Which line editing lib to use
 LIBEDIT_DESC=		Use libedit
 READLINE_DESC=		Use libreadline
-CAPIDOCS_BUILD_DEPENDS=	doxygen>0:devel/doxygen \
+CAPIDOCS_BUILD_DEPENDS=	doxygen>1.8.12,2:devel/doxygen \
 			dot:graphics/graphviz
 CAPIDOCS_CONFIGURE_ENABLE=	install-capi
 GMP_CONFIGURE_WITH=	gmp
Index: ruby23/Makefile
===================================================================
--- ruby23/Makefile	(revision 433785)
+++ ruby23/Makefile	(working copy)
@@ -55,7 +55,7 @@
 EDIT_DESC=		Which line editing lib to use
 LIBEDIT_DESC=		Use libedit
 READLINE_DESC=		Use libreadline
-CAPIDOCS_BUILD_DEPENDS=	doxygen>0:devel/doxygen \
+CAPIDOCS_BUILD_DEPENDS=	doxygen>1.8.12,2:devel/doxygen \
 			dot:graphics/graphviz
 CAPIDOCS_CONFIGURE_ENABLE=	install-capi
 GMP_CONFIGURE_WITH=	gmp