Makefile.am in rice-2.0.0

- old
+ new
@@ -21,27 +21,27 @@
 inheritance/Makefile: inheritance/extconf.rb ../config.status ../ruby/lib/mkmf-rice.rb
 	@RUBY@ $(RUBY_EXTCONF_OPTIONS) -C inheritance extconf.rb $(EXTCONF_OPTIONS)
 
 all: enum/Makefile map/Makefile inheritance/Makefile all_extensions
 
-all_extensions:
+all_extensions: $(addsuffix /Makefile,$(RICE_SAMPLES))
 	@for sample in $(RICE_SAMPLES); \
 	do \
-	  $(MAKE) -C $${sample} all; \
+	  ${MAKE} -C $${sample} all; \
 	done
 
 clean: enum/Makefile map/Makefile inheritance/Makefile clean_extensions
 
 clean_extensions:
 	@for sample in $(RICE_SAMPLES); \
 	do \
-	  $(MAKE) -C $${sample} clean; \
+	  ${MAKE} -C $${sample} clean; \
 	done
 
 distclean: enum/Makefile map/Makefile inheritance/Makefile distclean_extensions
 
 distclean_extensions:
 	@for sample in $(RICE_SAMPLES);
 	do \
-	  $(MAKE) -C $${sample} distclean; \
+	  ${MAKE} -C $${sample} distclean; \
 	done
 