Updatable cursor doubt

In CVS HEAD

workspace=# begin;
BEGIN
workspace=# declare cu cursor for select * from t1 for read only;
DECLARE CURSOR
workspace=# fetch cu; a
--- 1
(1 row)

workspace=# delete from t1 where current of cu;
DELETE 1
workspace=# commit;
COMMIT

Is this the intended behaviour? If so should we remove the 'READ ONLY' 
clause from the allowable syntax?

The documentation does not have 'READ ONLY' as part of the cursor syntax 
anymore.

Rgds,
Arul Shaji