diff --git a/docs/src/reference/docbook/ip.xml b/docs/src/reference/docbook/ip.xml
index b7f357fef9..369bbcd980 100644
--- a/docs/src/reference/docbook/ip.xml
+++ b/docs/src/reference/docbook/ip.xml
@@ -486,7 +486,19 @@
       from the response message by writing it to the connection.
     </para>
     <para>
-          The outbound gateway, after sending a message over the connection, waits for a response and
+     <note>
+      <para>
+       For the inbound gateway, care must be taken to retain, or populate, the
+       <emphasis>ip_connnection_id</emphasis> header because it is used to
+       correlate the message to a connection. Messages that originate at the
+       gateway will automatically have the header set. If the reply is 
+       constructed as a new message, you will need to set the header. The
+       header value can be captured from the incoming message.
+      </para>
+     </note>
+    </para>
+    <para>
+      The outbound gateway, after sending a message over the connection, waits for a response and
       constructs a response message and puts in on the reply channel.
       Communications over the connections are single-threaded. Users should be aware that only one
       message can be handled at a time and, if another thread attempts to send
@@ -562,12 +574,30 @@
     <para>
      To achieve high-volume throughput (avoiding the pitfalls of using gateways
      as mentioned above) you may consider configuring a pair of collaborating
-     outbound and inbound channel adapters. On the server side, message
+     outbound and inbound channel adapters.
+     Collaborating adapters can also be used (server-side or client-side) for
+     totally asynchronous communication (rather than with request/reply semantics).
+     On the server side, message
      correlation is automatically handled by the adapters because the inbound
      adapter adds a header allowing the outbound adapter to determine which
-     connection to use to send the reply message. On the client side, however, 
-     the application will have to provide its own correlation logic. This can
-     be done in a number of ways.
+     connection to use to send the reply message.
+    </para>
+    <para>
+     <note>
+      <para>
+       On the server side, care must be taken to populate the
+       <emphasis>ip_connnection_id</emphasis> header because it is used to
+       correlate the message to a connection. Messages that originate at the
+       inbound adapter will automatically have the header set. If you wish to
+       construct other messages to send, you will need to set the header. The
+       header value can be captured from an incoming message.
+      </para>
+     </note>
+    </para>
+    <para>
+     On the client side,
+     the application will have to provide its own correlation logic, if needed.
+     This can be done in a number of ways.
     </para>
     <para>
      If the message payload has some natural correlation data, such as a 
diff --git a/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpInboundGateway.java b/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpInboundGateway.java
index 9c74b8113d..8cf4d50b99 100644
--- a/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpInboundGateway.java
+++ b/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpInboundGateway.java
@@ -53,9 +53,12 @@ public class TcpInboundGateway extends MessagingGatewaySupport implements TcpLis
 			return false;
 		}
 		String connectionId = (String) message.getHeaders().get(IpHeaders.CONNECTION_ID);
-		TcpConnection connection = connections.get(connectionId);
+		TcpConnection connection = null;
+		if (connectionId != null) {
+			connection = connections.get(connectionId);
+		}
 		if (connection == null) {
-			logger.error("Connection " + connectionId + " not found when processing reply for " + message);
+			logger.error("Connection not found when processing reply " + reply + " for " + message);
 			return false;
 		}
 		try {
diff --git a/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpSendingMessageHandler.java b/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpSendingMessageHandler.java
index 83dd53b3b7..1370e92ed8 100644
--- a/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpSendingMessageHandler.java
+++ b/spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/TcpSendingMessageHandler.java
@@ -81,7 +81,10 @@ public class TcpSendingMessageHandler extends AbstractMessageHandler implements
 		if (this.serverConnectionFactory != null) {
 			// We don't own the connection, we are asynchronously replying
 			Object connectionId = message.getHeaders().get(IpHeaders.CONNECTION_ID);
-			TcpConnection connection = connections.get(connectionId);
+			TcpConnection connection = null;
+			if (connectionId != null) {
+				connection = connections.get(connectionId);
+			}
 			if (connection != null) {
 				try {
 					connection.send(message);
@@ -90,7 +93,7 @@ public class TcpSendingMessageHandler extends AbstractMessageHandler implements
 					connection.close();
 				}
 			} else {
-				logger.error("Unable to find incoming socket for " + message);
+				logger.error("Unable to find outbound socket for " + message);
 			}
 			return;
 		}