diff --git a/Makefile.am b/Makefile.am
index a04c903..875f498 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -8,6 +8,7 @@
 		SAX.c \
 		entities.c \
 		error.c \
+		error.h \
 		parser.c \
 		tester.c \
 		tree.c