diff --git a/src/vmime/security/cert/X509Certificate.hpp b/src/vmime/security/cert/X509Certificate.hpp
index 3aca9dd6..acf4ae21 100644
--- a/src/vmime/security/cert/X509Certificate.hpp
+++ b/src/vmime/security/cert/X509Certificate.hpp
@@ -85,6 +85,23 @@ public:
 	  */
 	static shared_ptr <X509Certificate> import(const byte_t* data, const size_t length);
 
+	/** Imports a DER or PEM encoded X.509 certificate.
+	  *
+	  * @param is input stream to read data from
+	  * @param certs the resulting list of certificates
+	  */
+	static void import(utility::inputStream& is,
+		std::vector <shared_ptr <X509Certificate> >& certs);
+
+	/** Imports a DER or PEM encoded X.509 certificate.
+	 *
+	 * @param data points to raw data
+	 * @param length size of data
+	 * @param certs the resulting list of certificates
+	 */
+	static void import(const byte_t* data, const size_t length,
+		std::vector <shared_ptr <X509Certificate> >& certs);
+
 	/** Exports this X.509 certificate to the specified format.
 	  *
 	  * @param os output stream into which write data
@@ -106,7 +123,7 @@ public:
 	  *
 	  * @return distinguished name of the certificate issuer, as a string
 	  */
-	const string getIssuerString() const;
+	virtual const string getIssuerString() const = 0;
 
 	/** Checks if this certificate has the given issuer.
 	  *
diff --git a/src/vmime/security/cert/gnutls/X509Certificate_GnuTLS.cpp b/src/vmime/security/cert/gnutls/X509Certificate_GnuTLS.cpp
index 478c1418..e23abc6d 100644
--- a/src/vmime/security/cert/gnutls/X509Certificate_GnuTLS.cpp
+++ b/src/vmime/security/cert/gnutls/X509Certificate_GnuTLS.cpp
@@ -56,6 +56,11 @@ struct GnuTLSX509CertificateInternalData
 		gnutls_x509_crt_deinit(cert);
 	}
 
+	void swap(gnutls_x509_crt_t to) {
+		gnutls_x509_crt_deinit(cert);
+		cert = to;
+	}
+
 
 	gnutls_x509_crt_t cert;
 };
@@ -128,6 +133,49 @@ shared_ptr <X509Certificate> X509Certificate::import
 }
 
 
+// static
+void X509Certificate::import(utility::inputStream& is,
+	std::vector <shared_ptr <X509Certificate> >& certs)
+{
+	byteArray bytes;
+	byte_t chunk[4096];
+
+	while (!is.eof())
+	{
+		const size_t len = is.read(chunk, sizeof(chunk));
+		bytes.insert(bytes.end(), chunk, chunk + len);
+	}
+
+	import(&bytes[0], bytes.size(), certs);
+}
+
+
+// static
+void X509Certificate::import(const byte_t* data, const size_t length,
+	std::vector <shared_ptr <X509Certificate> >& certs)
+{
+	gnutls_datum_t buffer;
+	buffer.data = const_cast <byte_t*>(data);
+	buffer.size = static_cast <unsigned int>(length);
+
+	unsigned int size = 1024;
+	gnutls_x509_crt_t x509[1024];
+
+	// Try DER format
+	if (gnutls_x509_crt_list_import(x509, &size, &buffer, GNUTLS_X509_FMT_DER, 0) < 0)
+
+		// Try PEM format
+		if (gnutls_x509_crt_list_import(x509, &size, &buffer, GNUTLS_X509_FMT_PEM, 0) < 0)
+			return;
+
+	for (unsigned int i = 0; i < size; i += 1) {
+		auto c = make_shared <X509Certificate_GnuTLS>();
+		c->m_data->swap(x509[i]);
+		certs.push_back(c);
+	}
+}
+
+
 void X509Certificate_GnuTLS::write
 	(utility::outputStream& os, const Format format) const
 {
diff --git a/src/vmime/security/cert/openssl/X509Certificate_OpenSSL.cpp b/src/vmime/security/cert/openssl/X509Certificate_OpenSSL.cpp
index 45481861..9ce09592 100644
--- a/src/vmime/security/cert/openssl/X509Certificate_OpenSSL.cpp
+++ b/src/vmime/security/cert/openssl/X509Certificate_OpenSSL.cpp
@@ -218,6 +218,41 @@ shared_ptr <X509Certificate> X509Certificate::import
 }
 
 
+// static
+void X509Certificate::import(utility::inputStream& is,
+	std::vector <shared_ptr <X509Certificate> >& certs)
+{
+	byteArray bytes;
+	byte_t chunk[4096];
+
+	while (!is.eof())
+	{
+		const size_t len = is.read(chunk, sizeof(chunk));
+		bytes.insert(bytes.end(), chunk, chunk + len);
+	}
+
+	import(&bytes[0], bytes.size(), certs);
+}
+
+
+// static
+void X509Certificate::import(const byte_t* data, const size_t length,
+	std::vector <shared_ptr <X509Certificate> >& certs)
+{
+
+	BIO* membio = BIO_new_mem_buf(const_cast <byte_t*>(data), static_cast <int>(length));
+	shared_ptr <X509Certificate_OpenSSL> cert = null;
+
+	while (true) {
+		cert = make_shared <X509Certificate_OpenSSL>();
+		if (!PEM_read_bio_X509(membio, &(cert->m_data->cert), 0, 0)) break;
+		certs.push_back(cert);
+	}
+
+	BIO_vfree(membio);
+}
+
+
 void X509Certificate_OpenSSL::write
 	(utility::outputStream& os, const Format format) const
 {