diff --git a/Makefile.am b/Makefile.am
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,9 +1,10 @@
 ACLOCAL_AMFLAGS = -I m4
 
-
+# both srcdir and builddir are needed because config.h ends up in builddir
 AM_CPPFLAGS = -DSYSCONFDIR='"$(sysconfdir)"' \
 	-DLOCALSTATEDIR='"$(localstatedir)"' \
-	-I$(top_srcdir)/src
+	-I$(top_srcdir)/src \
+	-I$(top_builddir)/src
 AM_CFLAGS = $(DISTLIBS_CFLAGS)
 LIBS = $(DISTLIBS_LIBS)