Short quetions: does Win XP 64 support test sign driver ?

Hi boys , Back to my question! I know the WHQL free for xp with other submission, i done that twice , i was just puzzled by SELF SIGN in XP 64 does not take effect , and the OS even can not recognize the sign in XP 64. In the XP , vista 32,64 ,win7 32,64 the test sign work fine .
My XP 64 OS is Windows XP professional x64 edition version 2003 SP2

WHERE does it [not] show the signer?

> In Device Manager , the properties of the device item . even i update driver in Device manager then selected the INF to be installed , there is no signed icon the the device list.

I generated the XP 64 CAT file by the command :
INF2CAT /driver: c:/ /os: XP_X64,Server2003_X64,Vista_X64

i check the inf and cat ,sys , it shows that the driver is signed

D:\WinDDK\7600.16385.1\bin\x86>Signtool verify /pa /v /c .cat .inf

Verifying: .inf
File is signed in catalog: .cat
Hash of file (sha1): AB22BFE4BDA08621B8744EE71D853F2746721B4F

Signing Certificate Chain:
Issued to: mykey
Issued by: mykey
Expires: Sun Jan 01 07:59:59 2040
SHA1 hash: E8F836C229E9E4FFEA0D46F3F2A862CFA823B61E

The signature is timestamped: Tue Sep 06 10:49:31 2011
Timestamp Verified by:
Issued to: Thawte Timestamping CA
Issued by: Thawte Timestamping CA
Expires: Fri Jan 01 07:59:59 2021
SHA1 hash: BE36A4562FB2EE05DBB3D32323ADF445084ED656

Issued to: VeriSign Time Stamping Services CA
Issued by: Thawte Timestamping CA
Expires: Wed Dec 04 07:59:59 2013
SHA1 hash: F46AC0C6EFBB8C6A14F55F09E2D37DF4C0DE012D

Issued to: VeriSign Time Stamping Services Signer - G2
Issued by: VeriSign Time Stamping Services CA
Expires: Fri Jun 15 07:59:59 2012
SHA1 hash: ADA8AAA643FF7DC38DD40FA4C97AD559FF4846DE

Successfully verified: .inf

Number of files successfully Verified: 1
Number of warnings: 0
Number of errors: 0