s3.basic fails with PS protocol, wrong errno

$ perl ./mtr s3.basic --ps-protocol

s3.basic                                 [ fail ]

        Test ended at 2022-08-19 17:55:33

CURRENT_TEST: s3.basic

mysqltest: At line 32: query 'insert into t1 values (1,1)' failed with wrong errno 1136: 'Column count doesn't match value count at row 1', instead of 1036...

The result from queries just before the failure was:

< snip >

select count(*) from t1;

count(*)

10000

select a,b from t1 where a between 10 and 20;

a	b

10	20

11	21

12	22

13	23

14	24

15	25

16	26

17	27

18	28

19	29

20	30

explain select * from t1 where a between 10 and 20;

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	range	a	a	5	NULL	#	Using index condition

insert into t1 values (1,1);