diff --git a/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java b/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
index 11cf843..9b4cf9d 100644
--- a/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
+++ b/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
@@ -70,7 +70,14 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
 
     private Message generateACKWithAR(Message message, String s) throws HL7Exception {
         try {
-            return message.generateACK(AcknowledgmentCode.AR, new HL7Exception(s, ErrorCode.UNKNOWN_KEY_IDENTIFIER));
+            Message returnMessage = message.generateACK(AcknowledgmentCode.AR, new HL7Exception(s, ErrorCode.UNKNOWN_KEY_IDENTIFIER));
+            HL7LogEntry entry = new HL7LogEntry();
+            entry.setMessage(returnMessage.encode());
+            entry.setSource("127.0.0.1:1234"); // TODO: Naja...
+            entry.setTimestamp(LocalDateTime.now());
+            entry.setDirection(HL7LogEntry.Direction.OUT);
+            HL7Utils.logHL7MessageToDatabase(entry);
+            return returnMessage;
         } catch (IOException e) {
             throw new HL7Exception(e);
         }