As reported by Lukas Fittl on gnupg-users, SPR 532 does now work correctly. I
dod some tests: After connecting the reader and running scdaemon as:
gpg-agent --daemon sh gpgsm --edit-key
I entered the command "verify" and got the same error as you. ThenI
stopped scdaemon (exit from the shell) and run the same comamnds
again. Now it works. However the right LED (enter pin) keeps lit
after the PIN has been entered.
Thus there is something wrong with the internal state of the reader.
I can't recall whether I noticed that in the past.