diff --git a/python/mozbuild/mozbuild/mach_commands.py b/python/mozbuild/mozbuild/mach_commands.py
index bd3fbe921f..6a7b28810a 100644
--- a/python/mozbuild/mozbuild/mach_commands.py
+++ b/python/mozbuild/mozbuild/mach_commands.py
@@ -1137,8 +1137,13 @@ class Mar(MachCommandBase):
 
     @Command('mar', category='post-build',
         description='Create the mar file for the built product for distribution.')
-    def mar(self):
-        return self._run_make(directory="./tools/update-packaging/", target='', ensure_exit_code=False)
+    @CommandArgument('--bz2', action='store_true',
+        help='Compress the mar package with old-style bz2 instead of xz')
+    def mar(self, bz2):
+        if bz2:
+          return self._run_make(directory="./tools/update-packaging/", target='mar-package-bz2', ensure_exit_code=False)
+        else:
+          return self._run_make(directory="./tools/update-packaging/", target='mar-package', ensure_exit_code=False)
 
 @CommandProvider
 class Install(MachCommandBase):
diff --git a/toolkit/mozapps/installer/package-name.mk b/toolkit/mozapps/installer/package-name.mk
index 680590b3c5..548a93b47f 100644
--- a/toolkit/mozapps/installer/package-name.mk
+++ b/toolkit/mozapps/installer/package-name.mk
@@ -80,6 +80,7 @@ PKG_UPDATE_BASENAME = $(PKG_BASENAME)
 CHECKSUMS_FILE_BASENAME = $(PKG_BASENAME)
 MOZ_INFO_BASENAME = $(PKG_BASENAME)
 PKG_UPDATE_PATH = $(PKG_PATH)
+BARE_MAR = $(PKG_UPDATE_PATH)$(PKG_UPDATE_BASENAME).mar
 COMPLETE_MAR = $(PKG_UPDATE_PATH)$(PKG_UPDATE_BASENAME).complete.mar
 # PARTIAL_MAR needs to be processed by $(wildcard) before you use it.
 PARTIAL_MAR = $(PKG_UPDATE_PATH)$(PKG_UPDATE_BASENAME).partial.*.mar
diff --git a/tools/update-packaging/Makefile.in b/tools/update-packaging/Makefile.in
index 4788a55752..a751ae3ce5 100644
--- a/tools/update-packaging/Makefile.in
+++ b/tools/update-packaging/Makefile.in
@@ -31,7 +31,7 @@ MAR_BIN	= $(DIST)/host/bin/mar$(HOST_BIN_SUFFIX)
 MBSDIFF_BIN	= $(DIST)/host/bin/mbsdiff$(HOST_BIN_SUFFIX)
 
 OVERRIDE_DEFAULT_GOAL := full-update
-full-update:: complete-patch
+full-update:: mar-package
 
 ifeq ($(OS_TARGET), WINNT)
 ifdef AB_CD
@@ -70,3 +70,23 @@ partial-patch:: $(dir-stage)
 ifdef MOZ_SIGN_CMD
 	$(MOZ_SIGN_CMD) -f mar '$(STAGE_DIR)/$(PKG_UPDATE_BASENAME).partial.$(SRC_BUILD_ID)-$(DST_BUILD_ID).mar'
 endif
+
+mar-package: $(call mkdir_deps,$(ABS_DIST)/$(PKG_STAGE_DIR))
+	@echo 'Creating update mar (xz compressed)...'
+	MAR=$(MAR_BIN) \
+	  $(srcdir)/make_full_update.sh \
+	  '$(DIST)/$(BARE_MAR)' \
+	  '$(PACKAGE_DIR)'
+ifdef MOZ_SIGN_CMD
+	$(MOZ_SIGN_CMD) -f mar '$(DIST)/$(BARE_MAR)'
+endif
+
+mar-package-bz2: $(call mkdir_deps,$(ABS_DIST)/$(PKG_STAGE_DIR))
+	@echo 'Creating update mar (bz2 compressed)...'
+	MAR_OLD_FORMAT=1 MAR=$(MAR_BIN) \
+	  $(srcdir)/make_full_update.sh \
+	  '$(DIST)/$(COMPLETE_MAR)' \
+	  '$(PACKAGE_DIR)'
+ifdef MOZ_SIGN_CMD
+	$(MOZ_SIGN_CMD) -f mar '$(DIST)/$(COMPLETE_MAR)'
+endif
\ No newline at end of file