Inconsistent results with bit type

CREATE TABLE t1(f1 bit(2) NOT NULL default b'10',f2 bit(14) NOT NULL default b'11110000111100');

INSERT INTO t1 (f1) VALUES (DEFAULT);

INSERT INTO t1 VALUES (b'',b''),('','');

SELECT HEX(f1), HEX(f2) FROM t1;

HEX(f1)	HEX(f2)

2	3C3C

2	3C8F <!-------- should be 0 0?

0	0

DROP TABLE t1;