Revisiting this I am no further on and would appreciate any pointers. Here's a trivial test:

use strict;
use warnings;

use Test::More tests => 1;

use Crypt::OpenPGP;

my $message = "Hello world!\n";
my $pgp = Crypt::OpenPGP->new ();
my $sig = $pgp->sign (
    Data        => $message,
    Clearsign   => 1,
    KeyID       => $ENV{GPG_SECRET_KEY},
    Passphrase  => $ENV{GPG_PP}
);

ok ($sig) or diag ($pgp->errstr);

[download]

With a valid secret key ID (in the form "ABCD1234") it bombs out as follows:

$ perl openpgp_sample.t 
1..1
encrypt: datasize not multiple of blocksize (16 bytes) at /usr/local/s
+hare/perl5/Crypt/OpenPGP/CFB.pm line 57.
# Looks like your test exited with 2 before it could output anything.

[download]

The keypair was created with gpg --gen-key for testing and is perfectly usable for signing via the gpg binary. What am I missing?

Some version info:

In reply to Re^2: GPG signing Issue by hippo
in thread GPG signing Issue by roperl

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