--- mercury-extras-0.13.1.orig/trailed_update/Mmakefile	2004-07-30 19:03:46.000000000 +1200
+++ mercury-extras-0.13.1/trailed_update/Mmakefile	2006-12-04 22:07:58.000000000 +1300
@@ -4,6 +4,10 @@
 # Public License - see the file COPYING.LIB in the Mercury distribution.
 #-----------------------------------------------------------------------------#
 
+LIBGRADES := 	$(foreach grade,$(LIBGRADES), \
+		$(subst .tr.,$(grade),$(findstring .tr.,$(grade))) \
+		$(filter %.tr,$(grade)))
+
 GRADEFLAGS += --use-trail
 
 # enable C debugging
@@ -30,6 +34,9 @@
 	cd samples && mmake $(MMAKEFLAGS) check
 	cd tests && mmake $(MMAKEFLAGS) check
 
+.PHONY: install
+install: libtrailed_update.install
+
 .PHONY: clean
 clean:
 	cd samples && mmake $(MMAKEFLAGS) clean