diff --git a/ncdump/Makefile.am b/ncdump/Makefile.am
index aa473cf17..5247ff685 100644
--- a/ncdump/Makefile.am
+++ b/ncdump/Makefile.am
@@ -138,7 +138,7 @@ ref_test_366_day_1900.cdl tst_hdf5_offset.sh run_ncgen_nc4_tests.sh	\
 tst_nccopy3_subset.sh ref_nccopy3_subset.nc ref_test_corrupt_magic.nc	\
 tst_ncgen_shared.sh tst_ncgen4.sh tst_ncgen4_classic.sh			\
 tst_ncgen4_diff.sh tst_ncgen4_cycle.sh tst_ctest.sh \
-tst_null_byte_padding.sh
+tst_null_byte_padding.sh ref_null_byte_padding_test.nc
 
 # The L512.bin file is file containing exactly 512 bytes each of value 0.
 # It is used for creating hdf5 files with varying offsets for testing.