diff --git a/lib/Crypt/OpenPGP/Buffer.pm b/lib/Crypt/OpenPGP/Buffer.pm
index 52103f3..39b4a4e 100644
--- a/lib/Crypt/OpenPGP/Buffer.pm
+++ b/lib/Crypt/OpenPGP/Buffer.pm
@@ -1,4 +1,7 @@
 package Crypt::OpenPGP::Buffer;
+
+use strict;
+
 use base qw( Data::Buffer );
 
 use Crypt::OpenPGP::Util qw( bin2mp mp2bin bitsize );
diff --git a/lib/Crypt/OpenPGP/Key/Public/ElGamal.pm b/lib/Crypt/OpenPGP/Key/Public/ElGamal.pm
index a00cfeb..b446eea 100644
--- a/lib/Crypt/OpenPGP/Key/Public/ElGamal.pm
+++ b/lib/Crypt/OpenPGP/Key/Public/ElGamal.pm
@@ -53,7 +53,7 @@ sub gen_k {
     my($p) = @_;
     ## XXX choose bitsize based on bitsize of $p
     my $bits = 198;
-    my $p_minus1 = $p - 1;
+    my $p_minus1 = Math::BigInt->new($p) - 1;
 
     my $k = Crypt::OpenPGP::Util::get_random_bigint($bits);
     while (1) {
diff --git a/lib/Crypt/OpenPGP/Key/Public/RSA.pm b/lib/Crypt/OpenPGP/Key/Public/RSA.pm
index ff78445..c2af056 100644
--- a/lib/Crypt/OpenPGP/Key/Public/RSA.pm
+++ b/lib/Crypt/OpenPGP/Key/Public/RSA.pm
@@ -64,9 +64,14 @@ sub verify {
 
 {
     my %ENCODING = (
-        MD2  => pack('H*', '3020300C06082A864886F70D020205000410'),
-        MD5  => pack('H*', '3020300C06082A864886F70D020505000410'),
-        SHA1 => pack('H*', '3021300906052B0E03021A05000414'),
+        MD2       => pack('H*', '3020300C06082A864886F70D020205000410'),
+        MD5       => pack('H*', '3020300C06082A864886F70D020505000410'),
+        SHA1      => pack('H*', '3021300906052B0E03021A05000414'),
+        SHA256    => pack('H*', '3031300d060960864801650304020105000420'),
+        SHA224    => pack('H*', '302d300d06096086480165030402040500041c'),
+        SHA384    => pack('H*', '3041300d060960864801650304020205000430'),
+        SHA512    => pack('H*', '3051300d060960864801650304020305000440'),
+        RIPEMD160 => pack('H*', '3021300906052b2403020105000414'),
     );
 
     sub encode {
diff --git a/t/14-sha2-verify.t b/t/14-sha2-verify.t
new file mode 100644
index 0000000..7c8dad6
--- /dev/null
+++ b/t/14-sha2-verify.t
@@ -0,0 +1,31 @@
+use strict;
+use Test::More tests => 2;
+
+use Crypt::OpenPGP;
+
+use vars qw( $SAMPLES );
+unshift @INC, 't/';
+require 'test-common.pl';
+use File::Spec;
+
+
+my $key_id = '43AA1C85';
+my $pass = "";
+my $uid = 'Test Key (SHA-512 key for Crypt::OpenPGP tests) <test@sha512.sig>';
+
+my $secring = File::Spec->catfile( $SAMPLES, 'gpg', 'sha2.sec' );
+my $pubring = File::Spec->catfile( $SAMPLES, 'gpg', 'sha2.pub' );
+my $pgp = Crypt::OpenPGP->new(
+    SecRing => $secring,
+    PubRing => $pubring,
+);
+isa_ok $pgp, 'Crypt::OpenPGP';
+
+{
+    diag 'sig generated by gpg with SHA512';
+
+    # Test a signature created by gnupg with SHA512 key
+    my $sig_file = File::Spec->catfile( $SAMPLES, 'sha2.asc' );
+    my $signer = $pgp->verify( SigFile => $sig_file );
+    is $signer, $uid, 'verified as signed by uid';
+}
diff --git a/t/samples/gpg/sha2.pub b/t/samples/gpg/sha2.pub
new file mode 100644
index 0000000..27d42e6
--- /dev/null
+++ b/t/samples/gpg/sha2.pub
@@ -0,0 +1,31 @@
+-----BEGIN PGP PUBLIC KEY BLOCK-----
+Version: GnuPG v1
+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+=JX1K
+-----END PGP PUBLIC KEY BLOCK-----
diff --git a/t/samples/gpg/sha2.sec b/t/samples/gpg/sha2.sec
new file mode 100644
index 0000000..cab9ace
--- /dev/null
+++ b/t/samples/gpg/sha2.sec
@@ -0,0 +1,58 @@
+-----BEGIN PGP PRIVATE KEY BLOCK-----
+Version: GnuPG v1
+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+=TbV3
+-----END PGP PRIVATE KEY BLOCK-----
diff --git a/t/samples/sha2.asc b/t/samples/sha2.asc
new file mode 100644
index 0000000..3d188ad
--- /dev/null
+++ b/t/samples/sha2.asc
@@ -0,0 +1,14 @@
+-----BEGIN PGP MESSAGE-----
+Version: GnuPG v1
+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+=WAvB
+-----END PGP MESSAGE-----