Commented by: @pcisar

According to my tests, this issue was not fixed in 2.0.1

create table T (A int, B int) ;
commit ;

insert into T values (1,1);
insert into T values (1,1);
insert into T values (2,2);
insert into T values (3,3);
insert into T values (null,null);
insert into T values (null,null);
insert into T values (4,4);
commit ;

select distinct A, B from T order by A, B nulls last ;

A B
============ ============
<null> <null>
1 1
2 2
3 3
4 4

select distinct A, B from T order by A nulls last ;

A B
============ ============
1 1
2 2
3 3
4 4
<null> <null>

select distinct A, B from T order by B nulls last ;

A B
============ ============
1 1
2 2
3 3
4 4
<null> <null>

Commented by: @dyemanov

The NULLS clause belongs to a single ORDER BY element, so if you want to see nulls at the end, you should write:
select distinct A, B from T order by A nulls last, B nulls last ;

Commented by: @pcisar

Fix verified, test added.