cisco invalid encrypted password!Why??

[guest]

Cisco6506e_1# conf t
Enter configuration commands, one per line. End with CNTL/Z.
Cisco6506e(config)#line console 0
Cisco6506e(config-line)#password ?
0 Specifies an UNENCRYPTED password will follow
7 Specifies a HIDDEN password will follow
LINE The UNENCRYPTED (cleartext) line password
Cisco6506e(config-line)#password 7 cisco
Invalid encrypted password: cisco

[guest]

Cisco6506e(config-line)#password 7 ?
WORD The HIDDEN line password string
Cisco6506e(config-line)#password 7 0226360B3D39（配置成功）
Cisco6506e(config-line)#

[guest]

Cisco6506e_1# conf t
Cisco6506e(config)#line vty 1 4
Cisco6506e(config)#pass cisco
Cisco6506e(config)#end
Cisco6506e_1# sh run | be line
line vty 1 4
password cisco（明文密码）

[guest]

Cisco6506e_1#conf t
Cisco6506e(config)#services password-encryption（打开加密服务）
Cisco6506e(config)#end
Cisco6506e_1#sh run | be line
line vty 1 4
password 7 061E173B540F594D5446582816(显示为加密密码)