diff --git a/Source/charon/payloads/ike_header.c b/Source/charon/payloads/ike_header.c
index 49f228f0b..3a1f23ff9 100644
--- a/Source/charon/payloads/ike_header.c
+++ b/Source/charon/payloads/ike_header.c
@@ -134,23 +134,14 @@ encoding_rule_t ike_header_encodings[] = {
 };
 
 /**
- * Implements ike_header_t's get_next_payload fuction.
- * See #ike_header_t.get_next_payload  for description.
+ * Implements payload_t's set_next_type function.
+ * See #payload_s.set_next_type for description.
  */
-static u_int8_t get_next_payload(private_ike_header_t *this)
+static status_t set_next_type(payload_t *this,payload_type_t type)
 {
-	return this->next_payload;	
+	((private_ike_header_t *)this)->next_payload = type;
+	return SUCCESS;
 }
-
-/**
- * Implements ike_header_t's set_next_payload fuction.
- * See #ike_header_t.set_next_payload  for description.
- */
-static void set_next_payload(private_ike_header_t *this, u_int8_t next_payload)
-{
-	this->next_payload = next_payload;
-}
-
 /**
  * Implements ike_header_t's get_initiator_spi fuction.
  * See #ike_header_t.get_initiator_spi  for description.
@@ -350,13 +341,11 @@ ike_header_t *ike_header_create()
 	this->public.payload_interface.get_encoding_rules = get_encoding_rules;
 	this->public.payload_interface.get_length = get_length;
 	this->public.payload_interface.get_next_type = get_next_type;
+	this->public.payload_interface.set_next_type = set_next_type;
 	this->public.payload_interface.get_type = get_type;
 	this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 	this->public.destroy = destroy;
 	
-
-	this->public.get_next_payload = (u_int8_t (*) (ike_header_t*))get_next_payload;
-	this->public.set_next_payload = (void (*) (ike_header_t*,u_int8_t))set_next_payload;
 	this->public.get_initiator_spi = (u_int64_t (*) (ike_header_t*))get_initiator_spi;
 	this->public.set_initiator_spi = (void (*) (ike_header_t*,u_int64_t))set_initiator_spi;
 	this->public.get_responder_spi = (u_int64_t (*) (ike_header_t*))get_responder_spi;
diff --git a/Source/charon/payloads/ike_header.h b/Source/charon/payloads/ike_header.h
index aa1d8f983..76f0e793b 100644
--- a/Source/charon/payloads/ike_header.h
+++ b/Source/charon/payloads/ike_header.h
@@ -97,14 +97,6 @@ struct ike_header_s {
 	 */
 	payload_t payload_interface;
 	
-	/**
-	 * @brief get the next payload type
-	 *
-	 * @param this 			ike_header_t object
-	 * @return 				next payload type
-	 */
-	u_int8_t (*get_next_payload) (ike_header_t *this);
-	
 	/**
 	 * @brief set the next payload
 	 *
diff --git a/Source/charon/payloads/payload.h b/Source/charon/payloads/payload.h
index f7b36fcff..2995a1631 100644
--- a/Source/charon/payloads/payload.h
+++ b/Source/charon/payloads/payload.h
@@ -194,6 +194,15 @@ struct payload_s {
 	 * @return 					type of next payload
 	 */
 	payload_type_t (*get_next_type) (payload_t *this);
+	
+	/**
+	 * @brief set type of next payload
+	 *
+	 * @param this 				calling object
+	 * @param type 				type of next payload
+	 * @return					SUCCESS in any case
+	 */
+	status_t (*set_next_type) (payload_t *this,payload_type_t type);
 
 	/**
 	 * @brief get length of payload 
diff --git a/Source/charon/payloads/proposal_substructure.c b/Source/charon/payloads/proposal_substructure.c
index ce9e2047c..8947b7446 100644
--- a/Source/charon/payloads/proposal_substructure.c
+++ b/Source/charon/payloads/proposal_substructure.c
@@ -184,6 +184,15 @@ static payload_type_t get_next_type(private_proposal_substructure_t *this)
 	return (this->next_payload);
 }
 
+/**
+ * Implements payload_t's set_next_type function.
+ * See #payload_s.set_next_type for description.
+ */
+static status_t set_next_type(private_proposal_substructure_t *this,payload_type_t type)
+{
+	return SUCCESS;
+}
+
 /**
  * Implements payload_t's get_length function.
  * See #payload_s.get_length for description.
@@ -349,6 +358,7 @@ proposal_substructure_t *proposal_substructure_create()
 	this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 	this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 	this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
+	this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;	
 	this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 	this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 	this->public.create_transform_substructure_iterator = (status_t (*) (proposal_substructure_t *,linked_list_iterator_t **,bool)) create_transform_substructure_iterator;
diff --git a/Source/charon/payloads/sa_payload.c b/Source/charon/payloads/sa_payload.c
index 34c75a25b..ab66e602e 100644
--- a/Source/charon/payloads/sa_payload.c
+++ b/Source/charon/payloads/sa_payload.c
@@ -64,6 +64,15 @@ struct private_sa_payload_s {
 	 * Proposals in this payload are stored in a linked_list_t
 	 */
 	linked_list_t * proposals;
+	
+	/**
+	 * @brief Computes the length of this payload.
+	 *
+	 * @param this 	calling private_sa_payload_t object
+	 * @return 		
+	 * 				SUCCESS in any case
+	 */
+	status_t (*compute_length) (private_sa_payload_t *this);
 };
 
 /**
@@ -146,12 +155,23 @@ static payload_type_t get_next_type(private_sa_payload_t *this)
 	return (this->next_payload);
 }
 
+/**
+ * Implements payload_t's set_next_type function.
+ * See #payload_s.set_next_type for description.
+ */
+static status_t set_next_type(private_sa_payload_t *this,payload_type_t type)
+{
+	this->next_payload = type;
+	return SUCCESS;
+}
+
 /**
  * Implements payload_t's get_length function.
  * See #payload_s.get_length for description.
  */
 static size_t get_length(private_sa_payload_t *this)
 {
+	this->compute_length(this);
 	return this->payload_length;
 }
 
@@ -170,7 +190,37 @@ static status_t create_proposal_substructure_iterator (private_sa_payload_t *thi
  */
 static status_t add_proposal_substructure (private_sa_payload_t *this,proposal_substructure_t *proposal)
 {
-	return (this->proposals->insert_last(this->proposals,(void *) proposal));
+	status_t status;
+	status = this->proposals->insert_last(this->proposals,(void *) proposal);
+	this->compute_length(this);
+	return status;
+}
+
+/**
+ * Implements private_sa_payload_t's compute_length function.
+ * See #private_sa_payload_s.compute_length for description.
+ */
+static status_t compute_length (private_sa_payload_t *this)
+{
+	linked_list_iterator_t *iterator;
+	status_t status;
+	size_t length = SA_PAYLOAD_HEADER_LENGTH;
+	status = this->proposals->create_iterator(this->proposals,&iterator,TRUE);
+	if (status != SUCCESS)
+	{
+		return length;
+	}
+	while (iterator->has_next(iterator))
+	{
+		payload_t *current_proposal;
+		iterator->current(iterator,(void **) &current_proposal);
+		length += current_proposal->get_length(current_proposal);
+	}
+	iterator->destroy(iterator);
+	
+	this->payload_length = length;
+		
+	return SUCCESS;
 }
 
 /*
@@ -187,12 +237,16 @@ sa_payload_t *sa_payload_create()
 	this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 	this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 	this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
+	this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
 	this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 	this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 	this->public.create_proposal_substructure_iterator = (status_t (*) (sa_payload_t *,linked_list_iterator_t **,bool)) create_proposal_substructure_iterator;
 	this->public.add_proposal_substructure = (status_t (*) (sa_payload_t *,proposal_substructure_t *)) add_proposal_substructure;
 	this->public.destroy = (status_t (*) (sa_payload_t *)) destroy;
 	
+	/* private functions */
+	this->compute_length = compute_length;
+	
 	/* set default values of the fields */
 	this->critical = SA_PAYLOAD_CRITICAL_FLAG;
 	this->next_payload = NO_PAYLOAD;
diff --git a/Source/charon/payloads/sa_payload.h b/Source/charon/payloads/sa_payload.h
index 51f283473..f589a1046 100644
--- a/Source/charon/payloads/sa_payload.h
+++ b/Source/charon/payloads/sa_payload.h
@@ -59,6 +59,10 @@ struct sa_payload_s {
 	 * @brief Creates an iterator of stored proposal_substructure_t objects.
 	 * 
 	 * @warning The created iterator has to get destroyed by the caller!
+	 * 
+	 * @warning When deleting an proposal using this iterator, 
+	 * 			the length of this transform substructure has to be refreshed 
+	 * 			by calling get_length()!
 	 *
 	 * @param this 			calling sa_payload_t object
 	 * @param iterator  		the created iterator is stored at the pointed pointer
diff --git a/Source/charon/payloads/transform_attribute.c b/Source/charon/payloads/transform_attribute.c
index b3128e82e..3dc714e78 100644
--- a/Source/charon/payloads/transform_attribute.c
+++ b/Source/charon/payloads/transform_attribute.c
@@ -131,6 +131,15 @@ static payload_type_t get_next_type(private_transform_attribute_t *this)
 	return (NO_PAYLOAD);
 }
 
+/**
+ * Implements payload_t's set_next_type function.
+ * See #payload_s.set_next_type for description.
+ */
+static status_t set_next_type(private_transform_attribute_t *this,payload_type_t type)
+{
+	return SUCCESS;
+}
+
 /**
  * Implements payload_t's get_length function.
  * See #payload_s.get_length for description.
@@ -233,6 +242,7 @@ transform_attribute_t *transform_attribute_create()
 	this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 	this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 	this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
+	this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
 	this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 	this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 	this->public.set_value = (status_t (*) (transform_attribute_t *,chunk_t value)) set_value;
diff --git a/Source/charon/payloads/transform_substructure.c b/Source/charon/payloads/transform_substructure.c
index 995f96ec7..bb7718a57 100644
--- a/Source/charon/payloads/transform_substructure.c
+++ b/Source/charon/payloads/transform_substructure.c
@@ -212,6 +212,15 @@ static bool get_is_last_transform (private_transform_substructure_t *this)
 	return ((this->next_payload == TRANSFORM_TYPE_VALUE) ? FALSE : TRUE);
 }
 
+/**
+ * Implements payload_t's set_next_type function.
+ * See #payload_s.set_next_type for description.
+ */
+static status_t set_next_type(private_transform_substructure_t *this,payload_type_t type)
+{
+	return SUCCESS;
+}
+
 /**
  * Implements transform_substructure_t's set_transform_type function.
  * See #transform_substructure_s.set_transform_type for description.
@@ -271,6 +280,8 @@ static status_t compute_length (private_transform_substructure_t *this)
 		length += current_attribute->get_length(current_attribute);
 	}
 	iterator->destroy(iterator);
+	
+	this->transform_length = length;
 		
 	return SUCCESS;
 }
@@ -289,6 +300,7 @@ transform_substructure_t *transform_substructure_create()
 	this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 	this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 	this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
+	this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;	
 	this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 	this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 	this->public.create_transform_attribute_iterator = (status_t (*) (transform_substructure_t *,linked_list_iterator_t **,bool)) create_transform_attribute_iterator;
diff --git a/Source/charon/payloads/transform_substructure.h b/Source/charon/payloads/transform_substructure.h
index ba4988073..661c94fec 100644
--- a/Source/charon/payloads/transform_substructure.h
+++ b/Source/charon/payloads/transform_substructure.h
@@ -59,8 +59,9 @@ struct transform_substructure_s {
 	 * 
 	 * @warning The created iterator has to get destroyed by the caller!
 	 * 
-	 * @warning When deleting an transform attribute, the length of this transform substructure
-	 * 			has to be refreshed with get_length!
+	 * @warning When deleting an transform attribute using this iterator, 
+	 * 			the length of this transform substructure has to be refreshed 
+	 * 			by calling get_length()!
 	 *
 	 * @param this 			calling transform_substructure_t object
 	 * @param iterator  		the created iterator is stored at the pointed pointer