--- a/Makefile	Thu Nov 07 15:24:23 2013 -0600
+++ b/Makefile	Tue Nov 05 09:43:36 2013 +0100
@@ -123,7 +123,10 @@
 	$(PYTHON) i18n/posplit i18n/hg.pot
 
 %.po: i18n/hg.pot
-	msgmerge --no-location --update $@ $^
+        # work on a temporary copy for never having a half completed target
+	cp $@ $@.tmp
+	msgmerge --no-location --update $@.tmp $^
+	mv -f $@~ $@
 
 .PHONY: help all local build doc clean install install-bin install-doc \
 	install-home install-home-bin install-home-doc dist dist-notests tests \