OpenPGP card decryption with 4096bit keys bugfix??

[Josef Schneider]

Hello,

first thing: I am not subscribed to this list, so please CC me in replies.

I recently bought a OpenPGP smart card and want to use 4096bit keys and
Windows.
This doesn't work for decrypting with any released gpg version!
There seems to be a patch to make it work at
http://lists.gnupg.org/pipermail/gnupg-users/2012-June/044868.html
Is this one line change the only thing that has to be changed to make it
work?
Compiling gpg2 for Windows is really hard it seems. I haven't got the
Gpg4win compilation to work because it needs some packages not available
on my debian sid based machine.
I am using the Gpg4win 2.1.1 Beta installer and want to change as little
as possible. I compiled libgpg-error and libassuan and switched out the
libassuan-0.dll
If this one line is the only change, this should be enough?! (except if
libassuan is also statically linked somewhere)
But the problem is still the same after the switch. The only commands
getting sent to the card when starting gpg --decrypt are:

> scdaemon[208]: chan_000001BC <- SERIALNO openpgp
> scdaemon[208]: chan_000001BC -> S SERIALNO
D27600012401020000050000XXXXXXXX 0
> scdaemon[208]: chan_000001BC -> OK
> scdaemon[208]: chan_000001BC <- RESTART
> scdaemon[208]: chan_000001BC -> OK

Even if I have to compile gpg2 as a whole I don't want to use the git
working copy, but the 2.0.19 source with only the patch to make
decryption with 4096bit Keys work.
So can someone tell me if this is the only change (then I probably am
doing something wrong) or if something else, and what, has to be changed.

Thanks,
Josef