diff --git a/jsstring.c b/jsstring.c
index 0bb2f22..9271b81 100644
--- a/jsstring.c
+++ b/jsstring.c
@@ -665,7 +665,7 @@ static void Sp_split(js_State *J)
 {
 	if (js_isundefined(J, 1)) {
 		js_newarray(J);
-		js_copy(J, 0);
+		js_pushstring(J, js_tostring(J, 0));
 		js_setindex(J, -2, 0);
 	} else if (js_isregexp(J, 1)) {
 		Sp_split_regexp(J);