diff --git a/MockFtpServer/.classpath b/MockFtpServer/.classpath
index 5188e0d..05ded44 100644
--- a/MockFtpServer/.classpath
+++ b/MockFtpServer/.classpath
@@ -21,5 +21,6 @@
 	<classpathentry kind="var" path="M2_REPO/easymock/easymock/1.2_Java1.3/easymock-1.2_Java1.3.jar"/>
 	<classpathentry kind="var" path="M2_REPO/xerces/xmlParserAPIs/2.6.2/xmlParserAPIs-2.6.2.jar"/>
 	<classpathentry exported="true" kind="con" path="GROOVY_SUPPORT"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/3"/>
 	<classpathentry kind="output" path="bin-groovy"/>
 </classpath>
diff --git a/MockFtpServer/src/main/groovy/org/mockftpserver/core/session/SessionKeys.groovy b/MockFtpServer/src/main/groovy/org/mockftpserver/core/session/SessionKeys.groovy
new file mode 100644
index 0000000..9aec814
--- /dev/null
+++ b/MockFtpServer/src/main/groovy/org/mockftpserver/core/session/SessionKeys.groovy
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2008 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ package org.mockftpserver.core.session
+
+/**
+ * Constants for names of properties (attributes) stored in the session.
+ */
+ class SessionKeys {
+
+     static final USERNAME = "username"
+     static final USER_ACCOUNT = "userAccount"
+     static final CURRENT_DIRECTORY = "currentDirectory"
+     static final RENAME_FROM = "renameFrom"
+ 
+}
\ No newline at end of file
diff --git a/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfiguration.groovy b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfiguration.groovy
new file mode 100644
index 0000000..56f89c0
--- /dev/null
+++ b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfiguration.groovy
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2008 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mockftpserver.fake
+
+import org.mockftpserver.fake.filesystem.FileSystem
+import org.mockftpserver.fake.user.UserAccount
+
+/**
+ * Interface for objects that provide access to server-specific information.
+ */
+interface ServerConfiguration {
+    
+    FileSystem getFileSystem()
+    void setFileSystem(FileSystem fileSystem)
+
+    ResourceBundle getReplyTextBundle()
+    void setReplyTextBundle(ResourceBundle resourceBundle)
+    
+    UserAccount getUserAccount(String username)
+    
+    String getTextForReplyCode(int replyCode)
+    
+}
\ No newline at end of file
diff --git a/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfigurationAware.groovy b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfigurationAware.groovy
new file mode 100644
index 0000000..b977d8a
--- /dev/null
+++ b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/ServerConfigurationAware.groovy
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2008 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mockftpserver.fake
+
+/**
+ * Interface for classes that provide setter and getter to access a ServerConfiguration instance.
+ */
+interface ServerConfigurationAware {
+     ServerConfiguration getServerConfiguration();
+     void setServerConfiguration(ServerConfiguration serverConfiguration);
+}
\ No newline at end of file
diff --git a/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/AbstractFakeCommandHandler.groovy b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/AbstractFakeCommandHandler.groovy
new file mode 100644
index 0000000..006ae0f
--- /dev/null
+++ b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/AbstractFakeCommandHandler.groovy
Binary files differ
diff --git a/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/UserCommandHandler.groovy b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/UserCommandHandler.groovy
new file mode 100644
index 0000000..e125739
--- /dev/null
+++ b/MockFtpServer/src/main/groovy/org/mockftpserver/fake/command/UserCommandHandler.groovy
Binary files differ
diff --git a/MockFtpServer/src/main/java/org/mockftpserver/core/command/Command.java b/MockFtpServer/src/main/java/org/mockftpserver/core/command/Command.java
index c0dd720..32c16cb 100644
--- a/MockFtpServer/src/main/java/org/mockftpserver/core/command/Command.java
+++ b/MockFtpServer/src/main/java/org/mockftpserver/core/command/Command.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2007 the original author or authors.
+ * Copyright 20078 the original author or authors.
  * 
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,7 @@
 package org.mockftpserver.core.command;
 
 import java.util.Arrays;
+import java.util.List;
 
 import org.mockftpserver.core.util.Assert;
 
@@ -35,7 +36,7 @@
     /**
      * Construct a new immutable instance with the specified command name and parameters
      * @param name - the command name; may not be null
-     * @param parameters - the command parameters; may be empty; may not benull
+     * @param parameters - the command parameters; may be empty; may not be null
      */
     public Command(String name, String[] parameters) {
         Assert.notNull(name, "name");
@@ -45,6 +46,15 @@
     }
 
     /**
+     * Construct a new immutable instance with the specified command name and parameters
+     * @param name - the command name; may not be null
+     * @param parameters - the command parameters; may be empty; may not be null
+     */
+    public Command(String name, List parameters) {
+        this(name, (String[]) parameters.toArray(new String[parameters.size()]));
+    }
+    
+    /**
      * @return the name
      */
     public String getName() {
diff --git a/MockFtpServer/src/main/java/org/mockftpserver/core/command/ReplyCodes.java b/MockFtpServer/src/main/java/org/mockftpserver/core/command/ReplyCodes.java
index 4bf03cf..8c0a437 100644
--- a/MockFtpServer/src/main/java/org/mockftpserver/core/command/ReplyCodes.java
+++ b/MockFtpServer/src/main/java/org/mockftpserver/core/command/ReplyCodes.java
@@ -53,6 +53,7 @@
     public static final int TYPE_OK = 200;
     public static final int USER_LOGGED_IN_OK = 230;
     public static final int USER_NEED_PASSWORD_OK = 331;
+    public static final int USER_NO_SUCH_USER = 530;
     
     public static final int SEND_DATA_INITIAL_OK = 150;
     public static final int SEND_DATA_FINAL_OK = 226;
diff --git a/MockFtpServer/src/test/groovy/org/mockftpserver/core/session/StubSession.groovy b/MockFtpServer/src/test/groovy/org/mockftpserver/core/session/StubSession.groovy
new file mode 100644
index 0000000..b498e19
--- /dev/null
+++ b/MockFtpServer/src/test/groovy/org/mockftpserver/core/session/StubSession.groovy
@@ -0,0 +1,153 @@
+/*
+ * Copyright 2008 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mockftpserver.core.session
+
+import java.net.InetAddress
+import java.util.Set
+
+/**
+ * Stub implementation of the {@link Session} interface for testing
+ * 
+ * @version $Revision: $ - $Date: $
+ *
+ * @author Chris Mair
+ */
+class StubSession implements Session {
+
+     Map attributes = [:]
+     List sentReplies = [ ]
+     
+    /**
+     * @see org.mockftpserver.core.session.Session#close()
+     */
+    public void close() {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#closeDataConnection()
+     */
+    public void closeDataConnection() {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#getAttribute(java.lang.String)
+     */
+    public Object getAttribute(String name) {
+        return attributes[name]
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#getAttributeNames()
+     */
+    public Set getAttributeNames() {
+        return attributes.keySet()
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#getClientHost()
+     */
+    public InetAddress getClientHost() {
+        return null
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#getServerHost()
+     */
+    public InetAddress getServerHost() {
+        return null
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#openDataConnection()
+     */
+    public void openDataConnection() {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#readData()
+     */
+    public byte[] readData() {
+        return null
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#removeAttribute(java.lang.String)
+     */
+    public void removeAttribute(String name) {
+        attributes.remove(name)
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#sendData(byte[], int)
+     */
+    public void sendData(byte[] data, int numBytes) {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#sendReply(int, java.lang.String)
+     */
+    public void sendReply(int replyCode, String replyText) {
+        sentReplies << [replyCode, replyText]
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#setAttribute(java.lang.String, java.lang.Object)
+     */
+    public void setAttribute(String name, Object value) {
+        attributes[name] = value
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#setClientDataHost(java.net.InetAddress)
+     */
+    public void setClientDataHost(InetAddress clientHost) {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#setClientDataPort(int)
+     */
+    public void setClientDataPort(int clientDataPort) {
+
+    }
+
+    /**
+     * @see org.mockftpserver.core.session.Session#switchToPassiveMode()
+     */
+    public int switchToPassiveMode() {
+        return 0
+    }
+
+    /**
+     * @see java.lang.Runnable#run()
+     */
+    public void run() {
+
+    }
+
+    //-------------------------------------------------------------------------
+    // Stub-specific API - Helper methods not part of Session interface
+    //-------------------------------------------------------------------------
+    
+    String toString() {
+        "StubSession[sentReplies=$sentReplies]"
+    }
+    
+}
diff --git a/MockFtpServer/src/test/groovy/org/mockftpserver/fake/StubServerConfiguration.groovy b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/StubServerConfiguration.groovy
new file mode 100644
index 0000000..3597de5
--- /dev/null
+++ b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/StubServerConfiguration.groovy
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2008 the original author or authors.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mockftpserver.fake
+
+import org.mockftpserver.fake.filesystem.FileSystem
+import org.mockftpserver.fake.ServerConfiguration
+import org.mockftpserver.fake.user.UserAccount
+
+/**
+ * Stub implementation of the {@link ServerConfiguration} interface for testing
+ * 
+ * @version $Revision: $ - $Date: $
+ *
+ * @author Chris Mair
+ */
+class StubServerConfiguration implements ServerConfiguration {
+
+     ResourceBundle replyTextBundle
+     Map userAccounts = [:]
+     
+     FileSystem getFileSystem() {
+         
+     }
+     
+     void setFileSystem(FileSystem fileSystem) {
+         
+     }
+
+     
+     UserAccount getUserAccount(String username) {
+         userAccounts[username]
+     }
+     
+     String getTextForReplyCode(int replyCode) {
+         return replyCode as String
+     }
+
+     //-------------------------------------------------------------------------
+     // Stub-specific API - Helper methods not part of ServerConfiguration interface
+     //-------------------------------------------------------------------------
+     
+}
diff --git a/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/AbstractCommandHandlerTest.groovy b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/AbstractCommandHandlerTest.groovy
new file mode 100644
index 0000000..d5de79e
--- /dev/null
+++ b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/AbstractCommandHandlerTest.groovy
Binary files differ
diff --git a/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/UserCommandHandlerTest.groovy b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/UserCommandHandlerTest.groovy
new file mode 100644
index 0000000..975d273
--- /dev/null
+++ b/MockFtpServer/src/test/groovy/org/mockftpserver/fake/command/UserCommandHandlerTest.groovy
Binary files differ
diff --git a/MockFtpServer/src/test/groovy/org/mockftpserver/test/AbstractGroovyTest.groovy b/MockFtpServer/src/test/groovy/org/mockftpserver/test/AbstractGroovyTest.groovy
index 7d9825a..9847bdb 100644
--- a/MockFtpServer/src/test/groovy/org/mockftpserver/test/AbstractGroovyTest.groovy
+++ b/MockFtpServer/src/test/groovy/org/mockftpserver/test/AbstractGroovyTest.groovy
@@ -46,7 +46,23 @@
          assert actualException.class == expectedExceptionClass, "Expected [${expectedExceptionClass.getName()}] but was [${actualException.class.name}]" 
          return actualException 
      } 
-         
+
+     /** 
+      * Assert that the specified code throws an exception with an error message
+      * containing the specified text. 
+      * @param text - the text expected within the exception message 
+      * @param code - the Closure containing the code to be executed, which is expected to throw an exception of the specified type
+      * @return the message from the thrown Exception 
+      * 
+      * @throws AssertionError - if no exception is thrown by the code or if the thrown 
+      * 	exception message does not contain the expected text 
+      */ 
+     protected String shouldFailWithMessageContaining(String text, Closure code) { 
+          def message = shouldFail(code)
+          assert message.contains(text)
+          return message
+     }
+          
      /** 
       * Write the specified message out to the log. Application-specific subclasses 
       * can override with application-specific logging behavior, if desired. 
diff --git a/MockFtpServer/src/test/java/org/mockftpserver/stub/command/CommandTest.java b/MockFtpServer/src/test/java/org/mockftpserver/stub/command/CommandTest.java
index d104885..a12175f 100644
--- a/MockFtpServer/src/test/java/org/mockftpserver/stub/command/CommandTest.java
+++ b/MockFtpServer/src/test/java/org/mockftpserver/stub/command/CommandTest.java
@@ -15,6 +15,8 @@
  */
 package org.mockftpserver.stub.command;
 
+import java.util.List;
+
 import org.apache.log4j.Logger;
 import org.mockftpserver.core.command.Command;
 import org.mockftpserver.core.util.AssertFailedException;
@@ -32,7 +34,7 @@
     private static final Logger LOG = Logger.getLogger(CommandTest.class);
     
     /**
-     * Test the constructor
+     * Test the Command(String,String[]) constructor
      */
     public void testConstructor() {
         final String[] PARAMETERS = array("123");
@@ -42,6 +44,17 @@
     }
     
     /**
+     * Test the Command(String,List) constructor
+     */
+    public void testConstructor_List() {
+        final List PARAMETERS_LIST = list("123");
+        final String[] PARAMETERS_ARRAY = array("123");
+        Command command = new Command("abc", PARAMETERS_LIST);
+        assertEquals("name", "abc", command.getName());
+        assertEquals("parameters String[]", PARAMETERS_ARRAY, command.getParameters());
+    }
+    
+    /**
      * Test the Constructor method, passing in a null name
      */
     public void testConstructor_NullName() {
@@ -59,7 +72,7 @@
      */
     public void testConstructor_NullParameters() {
         try {
-            new Command("OK", null);
+            new Command("OK", (String[])null);
             fail("Expected AssertFailedException");
         }
         catch (AssertFailedException expected) {