diff --git a/test/test_pkcs7.rb b/test/test_pkcs7.rb
index 93b62ce..eec72ff 100644
--- a/test/test_pkcs7.rb
+++ b/test/test_pkcs7.rb
@@ -53,4 +53,90 @@ def test_load_empty_pkcs7
     p7 = OpenSSL::PKCS7.new(EMPTY_PEM)
     assert_equal(EMPTY_PEM, p7.to_pem)
   end
+
+  PKCS7_ENCODED = <<END
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+END
+
+  PKCS7_DECODED = <<END
+-----BEGIN PKCS7-----
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+-----END PKCS7-----
+END
+
+  def test_signed_pkcs7_octet_sequence
+    p7signed = OpenSSL::PKCS7.new(PKCS7_ENCODED.unpack('m*').first)
+    p7signed.verify(nil, OpenSSL::X509::Store.new, nil, OpenSSL::PKCS7::NOVERIFY)
+
+    p7 = OpenSSL::PKCS7.new(p7signed.data)
+
+    assert_equal(p7.to_pem, PKCS7_DECODED)
+  end
+
+  def test_degenerate_pkcs7_add_cert
+    p7 = OpenSSL::PKCS7.new
+    cert = OpenSSL::X509::Certificate.new(CERT_PEM)
+    p7.type = 'signed'
+
+    assert_nothing_raised do
+      p7.add_certificate(cert)
+    end
+  end
 end