Compilation error using a view as the source data set for a MERGE statement

connect 'jdbc:derby:memory:db;create=true';

CREATE TABLE employee (
employee_id int,
first_name  VARCHAR(20),
last_name   VARCHAR(20),
dept_no     int,
salary      int);

create view v1employee as select * from employee;

CREATE TABLE bonuses (
employee_id int, bonus int DEFAULT 100);

create view v2bonuses as select * from bonuses;

-- compiles without the view
MERGE INTO bonuses B
USING employee E
ON B.employee_id = E.employee_id
WHEN MATCHED AND E.dept_no=20 THEN
  UPDATE SET B.bonus = E.salary * 0.1
WHEN NOT MATCHED AND dept_no=20 THEN
  INSERT (employee_id, bonus)
  VALUES (E.employee_id, E.salary * 0.05);

-- compilation error with the view
MERGE INTO bonuses B
USING v1employee E
ON B.employee_id = E.employee_id
WHEN MATCHED AND E.dept_no=20 THEN
  UPDATE SET B.bonus = E.salary * 0.1
WHEN NOT MATCHED AND dept_no=20 THEN
  INSERT (employee_id, bonus)
  VALUES (E.employee_id, E.salary * 0.05);