diff --git a/Makefile.am b/Makefile.am
index 3b585a87e8..fac53d5cc6 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -579,11 +579,11 @@ EXTRA_DIST += \
 
 libnm-core/nm-vpn-dbus-types.xml: libnm-core/nm-vpn-dbus-interface.h tools/enums-to-docbook.pl
 	@$(MKDIR_P) libnm-core/
-	$(AM_V_GEN) @PERL@ $(srcdir)/tools/enums-to-docbook.pl 'nm-vpn-dbus-types' 'VPN Plugin D-Bus API Types' $^ >$@
+	$(AM_V_GEN) @PERL@ $(srcdir)/tools/enums-to-docbook.pl 'nm-vpn-dbus-types' 'VPN Plugin D-Bus API Types' $< >$@
 
 libnm-core/nm-dbus-types.xml: libnm-core/nm-dbus-interface.h tools/enums-to-docbook.pl
 	@$(MKDIR_P) libnm-core/
-	$(AM_V_GEN) @PERL@ $(srcdir)/tools/enums-to-docbook.pl 'nm-dbus-types' 'NetworkManager D-Bus API Types' $^ >$@
+	$(AM_V_GEN) @PERL@ $(srcdir)/tools/enums-to-docbook.pl 'nm-dbus-types' 'NetworkManager D-Bus API Types' $< >$@
 
 BUILT_SOURCES += \
 	libnm-core/nm-vpn-dbus-types.xml \