diff --git a/Makefile.am b/Makefile.am
index f91c706fea..d32e787c32 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -279,13 +279,13 @@ uninstall-hook:
 	(cd docs && $(MAKE) uninstall)
 	(cd docs/libcurl && $(MAKE) uninstall)
 
-ca-bundle: scripts/mk-ca-bundle.pl
+ca-bundle: $(srcdir)/scripts/mk-ca-bundle.pl
 	@echo "generating a fresh ca-bundle.crt"
-	@perl $< -b -l -u lib/ca-bundle.crt
+	@perl $(srcdir)/scripts/mk-ca-bundle.pl -b -l -u lib/ca-bundle.crt
 
-ca-firefox: scripts/firefox-db2pem.sh
+ca-firefox: $(srcdir)/scripts/firefox-db2pem.sh
 	@echo "generating a fresh ca-bundle.crt"
-	$< lib/ca-bundle.crt
+	$(srcdir)/scripts/firefox-db2pem.sh lib/ca-bundle.crt
 
 checksrc:
 	(cd lib && $(MAKE) checksrc)