diff --git a/src/libcharon/encoding/message.c b/src/libcharon/encoding/message.c
index 1ee2cf81b..478f531ea 100644
--- a/src/libcharon/encoding/message.c
+++ b/src/libcharon/encoding/message.c
@@ -2513,7 +2513,7 @@ static status_t decrypt_payloads(private_message_t *this, keymat_t *keymat)
 			was_encrypted = "encrypted fragment payload";
 		}
 
-		if (payload_is_known(type, this->major_version) && !was_encrypted &&
+		if (type != PL_UNKNOWN && !was_encrypted &&
 			!is_connectivity_check(this, payload) &&
 			this->exchange_type != AGGRESSIVE)
 		{
diff --git a/src/libcharon/encoding/payloads/payload.c b/src/libcharon/encoding/payloads/payload.c
index a1cd2f945..f7c2754e0 100644
--- a/src/libcharon/encoding/payloads/payload.c
+++ b/src/libcharon/encoding/payloads/payload.c
@@ -97,6 +97,7 @@ ENUM_NEXT(payload_type_names, PLV1_NAT_D_DRAFT_00_03, PLV1_FRAGMENT, PLV2_FRAGME
 #endif /* ME */
 ENUM_NEXT(payload_type_names, PL_HEADER, PLV1_ENCRYPTED, PLV1_FRAGMENT,
 	"HEADER",
+	"UNKNOWN",
 	"PROPOSAL_SUBSTRUCTURE",
 	"PROPOSAL_SUBSTRUCTURE_V1",
 	"TRANSFORM_SUBSTRUCTURE",
@@ -167,6 +168,7 @@ ENUM_NEXT(payload_type_short_names, PLV1_NAT_D_DRAFT_00_03, PLV1_FRAGMENT, PLV2_
 #endif /* ME */
 ENUM_NEXT(payload_type_short_names, PL_HEADER, PLV1_ENCRYPTED, PLV1_FRAGMENT,
 	"HDR",
+	"UNKN",
 	"PROP",
 	"PROP",
 	"TRANS",
diff --git a/src/libcharon/encoding/payloads/payload.h b/src/libcharon/encoding/payloads/payload.h
index 920779bd1..72003894f 100644
--- a/src/libcharon/encoding/payloads/payload.h
+++ b/src/libcharon/encoding/payloads/payload.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2007 Tobias Brunner
+ * Copyright (C) 2007-2015 Tobias Brunner
  * Copyright (C) 2005-2006 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -263,6 +263,11 @@ enum payload_type_t {
 	 */
 	PL_HEADER = 256,
 
+	/**
+	 * Used to handle unknown or invalid payload types.
+	 */
+	PL_UNKNOWN,
+
 	/**
 	 * PLV2_PROPOSAL_SUBSTRUCTURE, IKEv2 proposals in a SA payload.
 	 */
diff --git a/src/libcharon/encoding/payloads/unknown_payload.c b/src/libcharon/encoding/payloads/unknown_payload.c
index 45b91fd0b..c69254fc0 100644
--- a/src/libcharon/encoding/payloads/unknown_payload.c
+++ b/src/libcharon/encoding/payloads/unknown_payload.c
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2015 Tobias Brunner
  * Copyright (C) 2005-2006 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -120,6 +121,12 @@ METHOD(payload_t, get_header_length, int,
 
 METHOD(payload_t, get_payload_type, payload_type_t,
 	private_unknown_payload_t *this)
+{
+	return PL_UNKNOWN;
+}
+
+METHOD(unknown_payload_t, get_type, payload_type_t,
+	private_unknown_payload_t *this)
 {
 	return this->type;
 }
@@ -181,6 +188,7 @@ unknown_payload_t *unknown_payload_create(payload_type_t type)
 				.destroy = _destroy,
 			},
 			.is_critical = _is_critical,
+			.get_type = _get_type,
 			.get_data = _get_data,
 			.destroy = _destroy,
 		},
diff --git a/src/libcharon/encoding/payloads/unknown_payload.h b/src/libcharon/encoding/payloads/unknown_payload.h
index 326b550cd..09341bcc7 100644
--- a/src/libcharon/encoding/payloads/unknown_payload.h
+++ b/src/libcharon/encoding/payloads/unknown_payload.h
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2015 Tobias Brunner
  * Copyright (C) 2005-2006 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -41,6 +42,13 @@ struct unknown_payload_t {
 	 */
 	payload_t payload_interface;
 
+	/**
+	 * Get the original payload type as sent by the peer.
+	 *
+	 * @return				type of the original payload
+	 */
+	payload_type_t (*get_type) (unknown_payload_t *this);
+
 	/**
 	 * Get the raw data of this payload, without
 	 * the generic payload header.
diff --git a/src/libcharon/sa/ikev2/task_manager_v2.c b/src/libcharon/sa/ikev2/task_manager_v2.c
index 298167703..4676867df 100644
--- a/src/libcharon/sa/ikev2/task_manager_v2.c
+++ b/src/libcharon/sa/ikev2/task_manager_v2.c
@@ -1184,15 +1184,17 @@ static status_t parse_message(private_task_manager_t *this, message_t *msg)
 		enumerator = msg->create_payload_enumerator(msg);
 		while (enumerator->enumerate(enumerator, &payload))
 		{
-			unknown = (unknown_payload_t*)payload;
-			type = payload->get_type(payload);
-			if (!payload_is_known(type, msg->get_major_version(msg)) &&
-				unknown->is_critical(unknown))
+			if (payload->get_type(payload) == PL_UNKNOWN)
 			{
-				DBG1(DBG_ENC, "payload type %N is not supported, "
-					 "but its critical!", payload_type_names, type);
-				status = NOT_SUPPORTED;
-				break;
+				unknown = (unknown_payload_t*)payload;
+				if (unknown->is_critical(unknown))
+				{
+					type = unknown->get_type(unknown);
+					DBG1(DBG_ENC, "payload type %N is not supported, "
+						 "but its critical!", payload_type_names, type);
+					status = NOT_SUPPORTED;
+					break;
+				}
 			}
 		}
 		enumerator->destroy(enumerator);