diff --git a/tests/Makefile.am b/tests/Makefile.am
index ca367c35d..83f378580 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -441,7 +441,7 @@ check-octave: $(O_XFAIL_TRS_FILES) $(O_TRS_FILES)
 
 %.o.tls : %.m
 	TOP_TEST_DIR="$(PWD)"  FILESTEM="$*" \
-		$(OCTAVE) --no-init-file --silent --no-history run_o_script 2>&1
+		$(OCTAVE) --no-init-file --silent --no-history run_o_script.m 2>&1
 
 
 clean-local: