When merging PO files, take into consideration translations in other PO

files of the same languages.  That way, similar or equal translations in
different programs are automatically propagated and the life of translators
becomes a little bit easier.

src/nls-global.mk

-# $PostgreSQL: pgsql/src/nls-global.mk,v 1.11 2005/12/09 21:19:34 petere Exp $
+# $PostgreSQL: pgsql/src/nls-global.mk,v 1.12 2006/04/05 13:40:15 petere Exp $
 
 # Common rules for Native Language Support (NLS)
 #
@@ -91,19 +91,22 @@ maintainer-check-po: $(PO_FILES)
 init-po: po/$(CATALOG_NAME).pot
 
 
+define merge-lang
+@printf 'merging $(1) '
+@if $(MSGMERGE) $(srcdir)/po/$(1).po $< -o po/$(1).po.new $(addprefix --compendium=,$(shell find $(top_srcdir) -name $(1).po -printf '%p ')); \
+then \
+    mv $(srcdir)/po/$(1).po po/$(1).po.old; \
+    mv po/$(1).po.new $(srcdir)/po/$(1).po; \
+else \
+    echo "msgmerge for $(1) failed"; \
+    rm -f po/$(1).po.new; \
+fi
+
+endef
+
 update-po: po/$(CATALOG_NAME).pot
 ifdef MSGMERGE
-	@for lang in $(LANGUAGES); do \
-	  echo "merging $$lang:"; \
-	  if $(MSGMERGE) $(srcdir)/po/$$lang.po $< -o po/$$lang.po.new; \
-	  then \
-	    mv $(srcdir)/po/$$lang.po po/$$lang.po.old; \
-	    mv po/$$lang.po.new $(srcdir)/po/$$lang.po; \
-	  else \
-	    echo "msgmerge for $$lang failed"; \
-	    rm -f po/$$lang.po.new; \
-	  fi; \
-	done
+	$(foreach lang,$(LANGUAGES),$(call merge-lang,$(lang)))
 else
 	@echo "You don't have 'msgmerge'." ; exit 1
 endif