Problem "Kobil Kaan Advanced" keypad [gnupg 2.0.18]

[Johannes Baiter]

I recently acquired a "Kobil Kaan Advanced" reader and am trying to
use it under Debian (unstable).
I have it working now up to the point where I can query the card
status, i.e. the reader works and the card is recognized correctly.
However, it seems that the built-in keypad of my reader does not work,
although according to the howto [1] it should do so:

$ gpg2 -d foo.txt.gpg
gpg: anonymous recipient; trying secret key <CENSORED> ...
scdaemon[21350]: updating slot 0 status: 0x0000->0x0007 (0->1)
scdaemon[21350]: fingerprint on card does not match requested one
scdaemon[21350]: app_decipher failed: Wrong secret key used
gpg: anonymous recipient; trying secret key <CENSORED2> ...
scdaemon[21350]: DBG: prompting for keypad entry '||Please enter the PIN'
gpg-agent[21349]: can't connect to the PIN entry module: IPC connect call failed
gpg: anonymous recipient; trying secret key <CENSORED3> ...
scdaemon[21350]: PIN callback returned error: Unexpected IPC command
scdaemon[21350]: app_decipher failed: Unexpected IPC command
gpg: anonymous recipient; trying secret key <CENSORED> ...
scdaemon[21350]: fingerprint on card does not match requested one
scdaemon[21350]: app_decipher failed: Wrong secret key used
gpg: anonymous recipient; trying secret key <CENSORED2> ...
scdaemon[21350]: DBG: prompting for keypad entry '||Please enter the PIN'
gpg-agent[21349]: can't connect to the PIN entry module: IPC connect call failed
gpg: anonymous recipient; trying secret key <CENSORED3> ...
scdaemon[21350]: PIN callback returned error: Unexpected IPC command
scdaemon[21350]: app_decipher failed: Unexpected IPC command
gpg: encrypted with RSA key, ID 00000000
gpg: encrypted with RSA key, ID 00000000
gpg: decryption failed: No secret key


[1] http://www.gnupg.org/howtos/card-howto/en/ch02s02.html