Index: src/main/java/quickfix/Session.java
===================================================================
--- src/main/java/quickfix/Session.java	(revision 627)
+++ src/main/java/quickfix/Session.java	(working copy)
@@ -25,28 +25,7 @@
 import java.util.Map;
 import java.util.WeakHashMap;
 
-import quickfix.field.BeginSeqNo;
-import quickfix.field.BeginString;
-import quickfix.field.BusinessRejectReason;
-import quickfix.field.EncryptMethod;
-import quickfix.field.EndSeqNo;
-import quickfix.field.GapFillFlag;
-import quickfix.field.HeartBtInt;
-import quickfix.field.MsgSeqNum;
-import quickfix.field.MsgType;
-import quickfix.field.NewSeqNo;
-import quickfix.field.OrigSendingTime;
-import quickfix.field.PossDupFlag;
-import quickfix.field.RefMsgType;
-import quickfix.field.RefSeqNum;
-import quickfix.field.RefTagID;
-import quickfix.field.ResetSeqNumFlag;
-import quickfix.field.SenderCompID;
-import quickfix.field.SendingTime;
-import quickfix.field.SessionRejectReason;
-import quickfix.field.TargetCompID;
-import quickfix.field.TestReqID;
-import quickfix.field.Text;
+import quickfix.field.*;
 
 /**
  * The Session is the primary FIX abstraction for message communication. It
@@ -193,6 +172,11 @@
      */
     public static final String SETTING_PERSIST_MESSAGES = "PersistMessages";
 
+    public static final String SETTING_LOGON_USERNAME = "Username";
+    public static final String SETTING_LOGON_PASSWORD = "Password";
+
+
+
     // @GuardedBy(sessions)
     private static final Map sessions = new WeakHashMap();
 
@@ -229,12 +213,15 @@
     private final boolean persistMessages;
     private final boolean checkCompID;
 
+    private final String username;
+    private final String password;
+
     Session(Application application, MessageStoreFactory messageStoreFactory, SessionID sessionID,
             DataDictionary dataDictionary, SessionSchedule sessionSchedule, LogFactory logFactory,
             MessageFactory messageFactory, int heartbeatInterval) {
         this(application, messageStoreFactory, sessionID, dataDictionary, sessionSchedule,
                 logFactory, messageFactory, heartbeatInterval, true, 120, true, false, false,
-                false, false, false, true, false, true, false);
+                false, false, false, true, false, true, false, null, null);
     }
 
     Session(Application application, MessageStoreFactory messageStoreFactory, SessionID sessionID,
@@ -243,7 +230,8 @@
             int maxLatency, boolean millisecondsInTimeStamp, boolean resetOnLogon,
             boolean resetOnLogout, boolean resetOnDisconnect, boolean resetWhenInitiatingLogon,
             boolean refreshMessageStoreAtLogon, boolean checkCompID,
-            boolean redundantResentRequestsAllowed, boolean persistMessages, boolean refreshOnLogon) {
+            boolean redundantResentRequestsAllowed, boolean persistMessages, boolean refreshOnLogon,
+            String username, String password) {
         this.application = application;
         this.sessionID = sessionID;
         this.sessionSchedule = sessionSchedule;
@@ -259,6 +247,8 @@
         this.checkCompID = checkCompID;
         this.redundantResentRequestsAllowed = redundantResentRequestsAllowed;
         this.persistMessages = persistMessages;
+        this.username = username;
+        this.password = password;
 
         synchronized (this) {
             if (logFactory != null) {
@@ -1310,12 +1300,26 @@
         if (isResetNeeded()) {
             logon.setBoolean(ResetSeqNumFlag.FIELD, true);
         }
+
+        addAuthenticationToLogon(logon);
+
         state.setLastReceivedTime(SystemTime.currentTimeMillis());
         state.clearTestRequestCounter();
         state.setLogonSent(true);
         return sendRaw(logon, 0);
     }
 
+    private void addAuthenticationToLogon(Message logon) {
+        if(dataDictionary==null || dataDictionary.isMsgField(MsgType.LOGON, Username.FIELD)) {
+            if(username!=null) {
+                logon.setField(Username.FIELD, username);
+            }
+            if(password!=null) {
+                logon.setField(Password.FIELD, password);
+            }
+        }
+    }
+
     /**
      * Logs out from session and closes the network connection.
      *
@@ -1529,6 +1533,7 @@
         }
         logon.setInt(HeartBtInt.FIELD, otherLogon.getInt(HeartBtInt.FIELD));
         initializeHeader(logon.getHeader());
+        addAuthenticationToLogon(logon);
         sendRaw(logon, 0);
         state.setLogonSent(true);
     }
Index: src/main/java/quickfix/DefaultSessionFactory.java
===================================================================
--- src/main/java/quickfix/DefaultSessionFactory.java	(revision 627)
+++ src/main/java/quickfix/DefaultSessionFactory.java	(working copy)
@@ -149,11 +149,15 @@
             int logonTimeout = getSetting(settings, sessionID, Session.SETTING_LOGON_TIMEOUT, 10);
             int logoutTimeout = getSetting(settings, sessionID, Session.SETTING_LOGON_TIMEOUT, 2);
 
+            String username = getSetting(settings, sessionID, Session.SETTING_LOGON_USERNAME, null);
+            String password = getSetting(settings, sessionID, Session.SETTING_LOGON_PASSWORD, null);
+
             Session session = new Session(application, messageStoreFactory, sessionID,
                     dataDictionary, new SessionSchedule(settings, sessionID), logFactory,
                     messageFactory, heartbeatInterval, checkLatency, maxLatency, millisInTimestamp,
                     resetOnLogon, resetOnLogout, resetOnDisconnect, resetOnLogon, refreshAtLogon,
-                    checkCompID, redundantResentRequestAllowed, persistMessages, refreshAtLogon);
+                    checkCompID, redundantResentRequestAllowed, persistMessages, refreshAtLogon,
+                    username, password);
 
             session.setLogonTimeout(logonTimeout);
             session.setLogoutTimeout(logoutTimeout);
@@ -186,4 +190,10 @@
                 : defaultValue;
     }
 
+    private String getSetting(SessionSettings settings, SessionID sessionID, String key,
+            String defaultValue) throws ConfigError, FieldConvertError {
+        return settings.isSetting(sessionID, key)
+                ? settings.getString(sessionID, key)
+                : defaultValue;
+    }
 }