Possible regression with STRICT MODE producing warning on WHERE Clause

CREATE  TABLE the_flags

(

lot_id varchar(255) PRIMARY KEY NOT NULL DEFAULT '' ,

flags binary(2) NOT NULL DEFAULT '\0\0'

);

INSERT INTO the_flags VALUES

('a', 5),

('b', 5),

('c', 5);

CREATE  TABLE the_new_flags

(

lot_id varchar(255) PRIMARY KEY NOT NULL DEFAULT '',

flags binary(2) NOT NULL DEFAULT '\0\0'

);

INSERT INTO the_new_flags

(

    SELECT lot_id, 1

    FROM the_flags

    WHERE ((cast( flags as binary) & 4)=4)

);