is($res, undef, 'cast from obsolete signature returns undef');
$res = eval { cast $c, undef };
-like($@, qr/Invalid\s+numeric\s+signature\s+at\s+\Q$0\E/, 'cast from undef croaks');
+like($@, qr/Invalid\s+wizard\s+object\s+at\s+\Q$0\E/, 'cast from undef croaks');
is($res, undef, 'cast from undef doesn\'t return anything');