diff --git xmlrpc_example/xmlrpc_example.info xmlrpc_example/xmlrpc_example.info
index 5a1f213..d19f482 100644
--- xmlrpc_example/xmlrpc_example.info
+++ xmlrpc_example/xmlrpc_example.info
@@ -1,5 +1,5 @@
 ; $Id$
 name = XMLRPC example
-description = This is an example of how to implement XML-RPC callbacks by implementing a validation suite.
+description = Demonstrates implementation of client and server communications using XML-RPC.
 package = Example modules
 core = 6.x
diff --git xmlrpc_example/xmlrpc_example.install xmlrpc_example/xmlrpc_example.install
new file mode 100644
index 0000000..7953474
--- /dev/null
+++ xmlrpc_example/xmlrpc_example.install
@@ -0,0 +1,23 @@
+<?php
+// $Id$
+
+/**
+ * @file
+ * Install, update and uninstall functions for the xmlrpc_example module.
+ */
+
+/**
+ * Implementation of hook_uninstall().
+ *
+ * Removes all the variables created by this module.
+ */
+function xmlrpc_example_uninstall() {
+  $variables = array(
+    'xmlrpc_example_server_min',
+    'xmlrpc_example_server_max',
+    'xmlrpc_example_alter_enabled',
+  );
+  foreach ($variables as $variable) {
+    variable_del($variable);
+  }
+}
diff --git xmlrpc_example/xmlrpc_example.module xmlrpc_example/xmlrpc_example.module
index 8f74d4e..6c5f6ed 100644
--- xmlrpc_example/xmlrpc_example.module
+++ xmlrpc_example/xmlrpc_example.module
@@ -1,74 +1,291 @@
 <?php
 // $Id$
-
 /**
  * @file
- * This is an example of how to implement XML-RPC callbacks by implementing a
- * validation suite.
+ * This is an example of how to implement and XML-RPC server by registering
+ * callbacks to specific methods and how to make xmlrpc calls using the builtin
+ * xmlrpc() factory provided by Drupal.
+ *
+ * For experimentation you may be interested in the
+ * @link http://drupal.org/project/xmlrpctester XMLRPC Tester module @endlink.
  *
- * Information on the test in this suite can be found at:
- * http://www.xmlrpc.com/validator1Docs
+ * Note that the @link http://drupal.org/project/services Services module @endlink
+ * is probably the more common way to do XMLRPC at this time.
+ *
+ * @see hook_xmlrpc()
+ * @see xmlrpc()
+ * @see xmlrpc_errno()
+ * @see xmlrpc_error_msg()
+ */
+
+// This is the common part of the module, implementing all the code required
+// for the client and the server part (most of this code is UI related). The
+// menu definition is the only part shared in this implementation.
+
+/**
+ * Implementation of hook_menu().
+ * Register all the demonstration forms.
+ */
+function xmlrpc_example_menu() {
+  // This is the server form menu entry. This form can be used to configure
+  // some options of the exposed services.
+  $items['examples/xmlrpc_server'] = array(
+    'title'           => 'XMLRPC Server',
+    'description'     => 'Demonstrates server side XMLRPC with Drupal',
+    'page callback'   => 'drupal_get_form',
+    'page arguments'  => array('xmlrpc_example_server_form'),
+    'access callback' => TRUE,
+    'weight'          => 0,
+  );
+  // This is the client form menu entry.
+  $items['examples/xmlrpc_client'] = array(
+    'title'           => 'XMLRPC Client',
+    'description'     => 'Demonstrates client side XMLRPC with Drupal',
+    'page callback'   => 'drupal_get_form',
+    'page arguments'  => array('xmlrpc_example_client_form'),
+    'access callback' => TRUE,
+    'weight'          => 1,
+  );
+  return $items;
+}
+
+
+// This is the server part of the module, implementing a simple and little
+// xmlrpc server with just two simple services. The serveris divided in two
+// different parts: the UI (settings form) and the xmlrpc implementation.
+//
+// The XMLRPC server will define two different services:
+//
+// - sub: perform the subtraction of two numbers. The minimum and maximum values
+// returned by the server can be configured in the settings form.
+// - add: perform the addition of two numbers. The minimum and maximum values
+// returned by the server can be configured in the settings form.
+//
+// If the result value for the operation is over the maximum limit, an error
+// 10001 is returned.
+// If the result value for the operation is below the minimum limit, an error
+// 10002 is returned.
+
+
+// User interface for the XMLRPC Server part.
+/**
+ * Present a form to configure the xmlrpc service options. In this case the max
+ * and min values for any of the operations (add or subtraction).
  */
+function xmlrpc_example_server_form() {
+  $form = array();
+  $form['explanation'] = array(
+    '#markup' => "<div>" . t("This is the configuration page for the demonstration XMLRPC Server.<br />Here you may define the maximum and minimum values for the add or subtraction exposed services.<br />") . "</div>",
+  );
+  $form['xmlrpc_example_server_min'] = array(
+    '#type' => 'textfield',
+    '#title' => t("Enter the minimum value returned by sub or add methods"),
+    '#description' => t("An xmlrpc error will result if they sum to more than 10 or the difference is less than 0."),
+    '#default_value' => variable_get('xmlrpc_example_server_min', 0),
+    '#size' => 5,
+    '#required' => TRUE,
+  );
+  $form['xmlrpc_example_server_max'] = array(
+    '#type' => 'textfield',
+    '#title' => t("Enter the maximum value returned by sub or add methods"),
+    '#default_value' => variable_get('xmlrpc_example_server_max', 10),
+    '#size' => 5,
+    '#required' => TRUE,
+  );
+  return system_settings_form($form);
+}
+
+// The following code is the XMLRPC implmentation of the server part. The fisrt
+// step is to define the methods. This methods should be associated to callbacks
+// that will be defined later.
 
 /**
- * Implementation of hook_xmlrpc().
+ * Implements hook_xmlrpc().
  *
- * This function provides Drupal with an array to map XML-RPC callbacks to the
+ * Provides Drupal with an array to map XML-RPC callbacks to the
  * functions implemented by this module.
+ *
+ * @see hook_xmlrpc()
  */
 function xmlrpc_example_xmlrpc() {
-  return (array(
-    'validator1.arrayOfStructsTest' => 'xmlrpc_example_arrayOfStructsTest',
-    'validator1.countTheEntities' => 'xmlrpc_example_countTheEntities',
-    'validator1.easyStructTest' => 'xmlrpc_example_easyStructTest',
-    'validator1.echoStructTest' => 'xmlrpc_example_echoStructTest',
-    'validator1.manyTypesTest' => 'xmlrpc_example_manyTypesTest',
-    'validator1.moderateSizeArrayCheck' => 'xmlrpc_example_moderateSizeArrayCheck',
-    'validator1.nestedStructTest' => 'xmlrpc_example_nestedStructTest',
-    'validator1.simpleStructReturnTest' => 'xmlrpc_example_simpleStructReturnTest'
-  ));
+  $methods[] =  array(
+    'xmlrpc_example.add',  // Method name
+    '_xmlrpc_example_server_add', // Callback to execute
+    array(                 // Array of types for output/input parameteres
+      'int',  // the type of the return value
+      'int',  // the type of the first argument
+      'int',  // the type of the second argument
+    ),
+    t('Returns the sum of the two arguments.') // Method description
+  );
+  // The subtract method is similiar to the addition
+  $methods[] =  array(
+    'xmlrpc_example.subtract',
+    '_xmlrpc_example_server_subtract',
+    array('int', 'int', 'int'),
+    t('Return difference of the two arguments.')
+  );
+
+  return $methods;
 }
 
-function xmlrpc_example_arrayOfStructsTest($array) {
-  $sum = 0;
-  foreach ($array as $struct) {
-    $sum += $struct['curly'];
+// Here are defined the callbacks for each method in the XMLRPC implementation
+// of the server: _xmlrpc_example.add and _xmlrpc_example.subtract
+
+/**
+ * Sum the two arguments.
+ *
+ * This is the callback for the xmlrpc_example.add xmlrpc method.
+ *
+ * @param $num1
+ * @param $num2
+ * @return
+ *   The sum of the arguments, or error if it is not in server defined bounds.
+ *
+ * @see xmlrpc_error()
+ */
+function _xmlrpc_example_server_add($num1, $num2) {
+  $sum = $num1 + $num2;
+  // If result is not within maximum and minimum limits, return corresponding error
+  if ($sum > variable_get('xmlrpc_example_server_max', 10)) {
+    return xmlrpc_error(10001, t("Result is over the higher limit defined by the server."));
+  }
+  if ($sum < variable_get('xmlrpc_example_server_min', 0)) {
+    return xmlrpc_error(10002, t("Result is under the lower limit defined by the server."));
   }
+  // Otherwise return the result.
   return $sum;
 }
 
-function xmlrpc_example_countTheEntities($string) {
-  return array(
-    'ctLeftAngleBrackets' => substr_count($string, '<'),
-    'ctRightAngleBrackets' => substr_count($string, '>'),
-    'ctAmpersands' => substr_count($string, '&'),
-    'ctApostrophes' => substr_count($string, "'"),
-    'ctQuotes' => substr_count($string, '"'),
-    );
+/**
+ * Return the difference of the two arguments.
+ *
+ * This is the callback for the xmlrpc_example.subtract xmlrpc method.
+ *
+ * @param numeric $num1
+ * @param numeric $num2
+ * @return
+ *   The difference of the two arguments, or error if it is not in server defined bounds.
+ *
+ * @see xmlrpc_error()
+ */
+function _xmlrpc_example_server_subtract($num1, $num2) {
+  $diference = $num1 - $num2;
+  // If result is not within maximum and minimum limits, return corresponding error
+  if ($diference > variable_get('xmlrpc_example_server_max', 10)) {
+    return xmlrpc_error(10001, t("Result is over the higher limit defined by the server."));
+  }
+  if ($diference < variable_get('xmlrpc_example_server_min', 0)) {
+    return xmlrpc_error(10002, t("Result is under the lower limit defined by the server."));
+  }
+  // Otherwise return the result.
+  return $diference;
 }
 
-function xmlrpc_example_easyStructTest($array) {
-  return $array["curly"] + $array["moe"] + $array["larry"];
-}
+// The server part of the module finishes here.
 
-function xmlrpc_example_echoStructTest($array) {
-  return $array;
-}
 
-function xmlrpc_example_manyTypesTest($args) {
-  $timestamp = mktime($args[4]->hour, $args[4]->minute, $args[4]->second, $args[4]->month, $args[4]->day, $args[4]->year);
-  return array($args[0], $args[1], $args[2], $args[3], xmlrpc_date($timestamp), xmlrpc_base64($args[5]));
-}
 
-function xmlrpc_example_moderateSizeArrayCheck($array) {
-  return array_shift($array) . array_pop($array);
+
+
+
+
+
+// This is the client part of the module. If defines a form with two input fields
+// to call xmlrcp_example.add or xmlrpc_example.subtract methods on this host.
+// Now begins the client/UI portion of the module.
+
+/**
+ * Present a form that makes use of xmlrpc services to add or subtract.
+ */
+function xmlrpc_example_client_form() {
+  $form = array();
+  $form['explanation'] = array(
+    '#markup' => "<div>" . t("The XMLRPC example demonstrates the use of the XMLRPC client in Drupal. <br/>It uses the xmlrpc() function to act as a client, calling itself for some defined methods.<br />An xmlrpc error will result if the result is out of bounds defined by the server.<br />") . "</div>",
+  );
+  $form['num1'] = array(
+    '#type' => 'textfield',
+    '#title' => t("Enter an integer"),
+    '#default_value' => 2,
+    '#size' => 5,
+    '#required' => TRUE,
+  );
+  $form['num2'] = array(
+    '#type' => 'textfield',
+    '#title' => t("Enter a second integer"),
+    '#default_value' => 2,
+    '#size' => 5,
+    '#required' => TRUE,
+  );
+  $form['add'] = array(
+    '#type' => 'submit',
+    '#value' => t("Add the integers"),
+    '#submit' => array('xmlrpc_example_client_add_submit'),
+  );
+  $form['subtract'] = array(
+    '#type' => 'submit',
+    '#value' => t("Subtract the integers"),
+    '#submit' => array('xmlrpc_example_client_subtract_submit'),
+  );
+  return $form;
 }
 
-function xmlrpc_example_nestedStructTest($array) {
-  return $array["2000"]["04"]["01"]["larry"] + $array["2000"]["04"]["01"]["moe"] + $array["2000"]["04"]["01"]["curly"];
+/**
+ * Submit: query the xmlrpc endpoint for the method xmlrpc_example.add
+ * and report the result.
+ * @param $form
+ * @param $form_state
+ *
+ * @see xmlrpc()
+ * @see xmlrpc_errno()
+ * @see xmlrpc_error_msg()
+ */
+function xmlrpc_example_client_add_submit($form, &$form_state) {
+  // First define the endpoint of the xmlrcp service, in this case is our
+  // own server.
+  $server = url($GLOBALS['base_url'] . "/xmlrpc.php");
+  // Then we should pass the method and the arguments to the xmlrpc client.
+  // Make the xmlrpc request and process the results.
+  $result = xmlrpc(
+    $server,                             // Url of the xmlrpc endpoint
+    'xmlrpc_example.add',                // Method to call
+    (int) $form_state['values']['num1'], // argument 1
+    (int) $form_state['values']['num2']  // argument 2...
+  );
+
+  if ($result === FALSE) {
+    drupal_set_message(t("Error return from xmlrpc(): Error: @errno, Message: @message", array('@errno' => xmlrpc_errno(), '@message' => xmlrpc_error_msg())));
+  }
+  else {
+    drupal_set_message(t("The XMLRPC server returned this response: @response", array('@response' => print_r($result, TRUE))));
+  }
 }
 
-function xmlrpc_example_simpleStructReturnTest($number) {
-  return array("times10" => ($number*10), "times100" => ($number*100), "times1000" => ($number*1000));
+/**
+ * Submit for subtraction: Call the xmlrpc method and report the result.
+ * @param $form
+ * @param $form_state
+ *
+ * @see xmlrpc()
+ * @see xmlrpc_errno()
+ * @see xmlrpc_error_msg()
+ * @see xmlrpc_example_client_add_submit()
+ */
+function xmlrpc_example_client_subtract_submit($form, &$form_state) {
+  $server = url($GLOBALS['base_url'] . "/xmlrpc.php");
+  $result = xmlrpc(
+    $server,
+    'xmlrpc_example.subtract',
+    (int) $form_state['values']['num1'],
+    (int) $form_state['values']['num2']
+  );
+
+  if ($result === FALSE) {
+    drupal_set_message(t("Error return from xmlrpc(): Error: @errno, Message: @message", array('@errno' => xmlrpc_errno(), '@message' => xmlrpc_error_msg())));
+  }
+  else {
+    drupal_set_message(t("The XMLRPC server returned this response: @response", array('@response' => print_r($result, TRUE))));
+  }
 }
 
+// End of client part of the module.
\ No newline at end of file
diff --git xmlrpc_example/xmlrpc_example.test xmlrpc_example/xmlrpc_example.test
new file mode 100644
index 0000000..83f703f
--- /dev/null
+++ xmlrpc_example/xmlrpc_example.test
@@ -0,0 +1,90 @@
+<?php
+// $Id$
+
+/**
+ * @file
+ * Test case for the xmlrpc example module.
+ *
+ * This file contains the test cases to check if module is performing as
+ * expected.
+ *
+ */
+class XmlrpcExampleTestCase extends DrupalWebTestCase {
+  protected $xmlrpc_url;
+
+  public static function getInfo() {
+    return array(
+      'name' => 'XMLRPC example functionality',
+      'description' => 'Test xmlrpc service implementation.',
+      'group' => 'Examples',
+    );
+  }
+
+  /**
+   * Enable module.
+   */
+  function setUp() {
+    parent::setUp('xmlrpc_example');
+
+    // Init common variables.
+    global $base_url;
+    $this->xmlrpc_url = url($base_url . '/xmlrpc.php', array('external' => TRUE));
+  }
+
+  /**
+   * Perform several calls the xmlrpc inteface to test the services.
+   */
+  function testXmlrpcExampleBasic() {
+    // Unit test functionality.
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.add', 3, 4);
+    $this->assertEqual($result, 7, t('Successfully added 3+4 = 7'));
+
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.subtract', 4, 3);
+    $this->assertEqual($result, 1, t('Successfully subtracted 4-3 = 1'));
+
+    // Verify default limits
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.subtract', 3, 4);
+    $this->assertEqual(xmlrpc_errno(), 10002, t('Results below minimum return error: 10002'));
+
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.add', 7, 4);
+    $this->assertEqual(xmlrpc_errno(), 10001, t('Results beyond maximum return error: 10001'));
+  }
+
+
+  /**
+   * Perform several calls using xmlrpc UI client
+   */
+  function testXmlrpcExampleClient() {
+    // Now test the UI.
+    $edit = array('num1' => 3, 'num2' => 5);
+    $this->drupalPost('examples/xmlrpc_client', $edit, t('Add the integers'));
+    $this->assertText(t("The XMLRPC server returned this response: @num", array('@num' => 8)));
+
+    $edit = array('num1' => 8, 'num2' => 3);
+    $this->drupalPost('examples/xmlrpc_client', $edit, t('Subtract the integers'));
+    $this->assertText(t("The XMLRPC server returned this response: @num", array('@num' => 5)));
+  }
+
+  /**
+   * Perform several xmlrpc requests changing server settings
+   */
+  function testXmlrpcExampleServer() {
+    // Now test the UI.
+    $options = array('xmlrpc_example_server_min' => 3, 'xmlrpc_example_server_max' => 7);
+    $this->drupalPost('examples/xmlrpc_server', $options, t('Save configuration'));
+    $this->assertText(t("The configuration options have been saved"), t("Results limited to >= 3 and <= 7"));
+
+    $edit = array('num1' => 8, 'num2' => 3);
+    $this->drupalPost('examples/xmlrpc_client', $edit, t('Subtract the integers'));
+    $this->assertText(t("The XMLRPC server returned this response: @num", array('@num' => 5)));
+
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.add', 3, 4);
+    $this->assertEqual($result, 7, t('Successfully added 3+4 = 7'));
+
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.subtract', 4, 3);
+    $this->assertEqual(xmlrpc_errno(), 10002, t('subtracting 4-3 = 1 returns: 10002'));
+
+    $result = xmlrpc($this->xmlrpc_url, 'xmlrpc_example.add', 7, 4);
+    $this->assertEqual(xmlrpc_errno(), 10001, t('Adding 7 + 4 = 11 returns: 10001'));
+  }
+}