diff --git a/librfc822/Makefile.am b/librfc822/Makefile.am
index 71cb6f4..49210c5 100644
--- a/librfc822/Makefile.am
+++ b/librfc822/Makefile.am
@@ -9,10 +9,12 @@ librfc822_a_SOURCES = address.y address_scan.l address_sep.c decomment.c
 
 noinst_PROGRAMS   = test
 test_SOURCES      = test.c ../libmpools/mpools.c ../liblists/lists.c
-test_CPPFLAGS     = -I${srcdir}/../libgnu
+test_CPPFLAGS     = -I$(srcdir)/../libgnu
 test_LDADD        = librfc822.a ../libgnu/libgnu.a
 
 EXTRA_DIST        = testaddresslines parse_address.c
 
 DISTCLEANFILES    = address.c address_scan.c
 MAINTAINERCLEANFILES = Makefile.in
+
+$(builddir)/address_scan.o : $(builddir)/address.h