OpenPGP Card useing sha256 failed !!

[Po-Wen Chi]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I have a OpenPGP Card.
I have already produced key pear on this card .
But go wrong when I will sign with this card.
If using SHA-1 will be carried out normally.
But if appoint to use SHA-256 , will present wrong information .
The following is course and information operated.

Excuse me, who can tell me what the matter is?

very thanks.

== SHA-1 OK! ==
cmd> gpg --digest-algo sha1 -u 4a7d9528 --clearsign a.txt
gpg: detected reader `CASTLES EZ100PU 0'
gpg: signatures created so far: 6

Please enter the PIN
[sigs done: 6]


== SHA-256 failed ==
cmd> gpg --digest-algo sha256 -u 4a7d9528 --clearsign a.txt
gpg: detected reader `CASTLES EZ100PU 0'
gpg: signing failed: invalid argument
gpg: a.txt: clearsign failed: invalid argument
- --
This E-mail use UTF-8 character code
Po-Wen Chi(紀博文) <http://www.pwchi.info/>
一個自信、勇敢、熱誠的男子漢。
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