--- a/suite/build.mk
+++ b/suite/build.mk
@@ -79,16 +79,19 @@ tier_app_dirs += \
 endif # COMM_BUILD
 
 installer:
 	@$(MAKE) -C suite/installer installer
 
 package:
 	@$(MAKE) -C suite/installer
 
+package-compare:
+	@$(MAKE) -C suite/installer package-compare
+
 install::
 	@$(MAKE) -C suite/installer install
 
 ifndef COMM_BUILD
 # mochitests need to be run from the Mozilla build system
 ifdef ENABLE_TESTS
 # Implemented in testing/testsuite-targets.mk
 mochitest-browser-chrome:

--- a/suite/installer/Makefile.in
+++ b/suite/installer/Makefile.in
@@ -96,12 +96,25 @@ MOZ_PKG_MAC_BACKGROUND=branding/backgrou
 MOZ_PKG_MAC_ICON=branding/disk.icns
 MOZ_PKG_MAC_EXTRA=--format UDBZ \
                   --symlink "/Applications: " \
                   --copy "bin/README.txt"
 endif
 
 include $(MOZILLA_SRCDIR)/toolkit/mozapps/installer/packager.mk
 
+ifeq (WINNT,$(OS_ARCH))
+PKGCOMP_FIND_OPTS = 
+else
+PKGCOMP_FIND_OPTS = -L
+endif
+
+package-compare::
+ifdef MOZ_PKG_MANIFEST_P
+	cd $(DIST); find $(PKGCOMP_FIND_OPTS) bin -type f | sort > bin-list.txt
+	grep "^bin" $(MOZ_PKG_MANIFEST) | sed -e 's/\\/\//g' | sort > $(DIST)/pack-list.txt
+	-diff -u $(DIST)/pack-list.txt $(DIST)/bin-list.txt
+endif
+
 installer: removed-files
 ifdef INSTALLER_DIR
 	$(MAKE) -C $(INSTALLER_DIR)
 endif