diff -urNad mauve.orig/mauve-20140821/debian/rules mauve/mauve-20140821/debian/rules
--- mauve.orig/mauve-20140821/debian/rules	2015-02-12 23:49:53.696111641 +0000
+++ mauve/mauve-20140821/debian/rules	2015-02-12 23:54:10.779458633 +0000
@@ -4,6 +4,7 @@
 # Uncomment this to turn on verbose mode.
 #export DH_VERBOSE=1
 
+BUILD_DATE := $(shell dpkg-parsechangelog --show-field Date)
 
 build: build-stamp
 build-arch: build-stamp
@@ -29,8 +30,8 @@
 	mkdir -p debian/mauve/usr/src/mauve
 	cp -a $(filter-out debian, $(wildcard .??* *)) \
 		debian/mauve/usr/src/mauve/
-	tar -c --gzip -f $(CURDIR)/debian/mauve/usr/src/mauve.tar.gz \
-		-C debian/mauve/usr/src mauve
+	GZIP="-9n" tar -c --gzip -f $(CURDIR)/debian/mauve/usr/src/mauve.tar.gz \
+		-C debian/mauve/usr/src --mtime="$(BUILD_DATE)" mauve
 	rm -rf debian/mauve/usr/src/mauve
 
 # Build architecture-independent files here.