Index: lib/completion/data_object.php
===================================================================
--- lib/completion/data_object.php	(revision 1.3)
+++ lib/completion/data_object.php	(revision )
@@ -104,15 +104,19 @@
      * @param array $params associative arrays varname=>value
      * @return object data_object instance or false if none found.
      */
-    public static abstract function fetch($params);
+    public static function fetch($params) {
+        throw new coding_exception('fetch() method needs to be overridden in each subclass of data_object');
+    }
 
     /**
      * Finds and returns all data_object instances based on params.
      *
      * @param array $params associative arrays varname=>value
-     * @return array array of data_object insatnces or false if none found.
+     * @return array array of data_object instances or false if none found.
      */
-    public static function fetch_all($params) {}
+    public static function fetch_all($params) {
+        throw new coding_exception('fetch_all() method needs to be overridden in each subclass of data_object');
+    }
 
     /**
      * Factory method - uses the parameters to retrieve matching instance from the DB.
Index: lib/ddl/sql_generator.php
===================================================================
--- lib/ddl/sql_generator.php	(revision 1.36)
+++ lib/ddl/sql_generator.php	(revision )
@@ -1188,7 +1188,7 @@
      * @return array of reserved words
      */
     public static function getReservedWords() {
-        return array();
+        throw new coding_exception('getReservedWords() method needs to be overridden in each subclass of sql_generator');
     }
 
     /**
Index: lib/googleapi.php
===================================================================
--- lib/googleapi.php	(revision 1.14)
+++ lib/googleapi.php	(revision )
@@ -42,12 +42,14 @@
  * @copyright Dan Poltawski <talktodan@gmail.com>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-abstract class google_auth_request extends curl{
+abstract class google_auth_request extends curl {
     protected $token = '';
     private $persistantheaders = array();
 
-    // Must be overriden with the authorization header name
-    public abstract static function get_auth_header_name();
+    // Must be overridden with the authorization header name
+    public static function get_auth_header_name() {
+        throw new coding_exception('get_auth_header_name() method needs to be overridden in each subclass of google_auth_request');
+    }
 
     protected function request($url, $options = array()){
         if($this->token){
Index: lib/grade/grade_object.php
===================================================================
--- lib/grade/grade_object.php	(revision 1.55)
+++ lib/grade/grade_object.php	(revision )
@@ -119,7 +119,9 @@
      * @param array $params associative arrays varname=>value
      * @return object grade_object instance or false if none found.
      */
-    public static abstract function fetch($params);
+    public static function fetch($params) {
+        throw new coding_exception('fetch() method needs to be overridden in each subclass of grade_object');
+    }
 
     /**
      * Finds and returns all grade_object instances based on params.
@@ -128,7 +130,9 @@
      * @param array $params associative arrays varname=>value
      * @return array array of grade_object instances or false if none found.
      */
-    public static abstract function fetch_all($params);
+    public static function fetch_all($params) {
+        throw new coding_exception('fetch_all() method needs to be overridden in each subclass of grade_object');
+    }
 
     /**
      * Factory method - uses the parameters to retrieve matching instance from the DB.
Index: backup/moodle2/restore_activity_task.class.php
===================================================================
--- backup/moodle2/restore_activity_task.class.php	(revision 1.8)
+++ backup/moodle2/restore_activity_task.class.php	(revision )
@@ -216,13 +216,17 @@
      * Define the contents in the activity that must be
      * processed by the link decoder
      */
-    abstract static public function define_decode_contents();
+    static public function define_decode_contents() {
+        throw new coding_exception('define_decode_contents() method needs to be overridden in each subclass of restore_activity_task');
+    }
 
     /**
      * Define the decoding rules for links belonging
      * to the activity to be executed by the link decoder
      */
-    abstract static public function define_decode_rules();
+    static public function define_decode_rules() {
+        throw new coding_exception('define_decode_rules() method needs to be overridden in each subclass of restore_activity_task');
+    }
 
 // Protected API starts here
 
Index: backup/moodle2/restore_block_task.class.php
===================================================================
--- backup/moodle2/restore_block_task.class.php	(revision 1.4)
+++ backup/moodle2/restore_block_task.class.php	(revision )
@@ -152,13 +152,17 @@
      * Define the contents in the activity that must be
      * processed by the link decoder
      */
-    abstract static public function define_decode_contents();
+    static public function define_decode_contents() {
+        throw new coding_exception('define_decode_contents() method needs to be overridden in each subclass of restore_block_task');
+    }
 
     /**
      * Define the decoding rules for links belonging
      * to the activity to be executed by the link decoder
      */
-    abstract static public function define_decode_rules();
+    static public function define_decode_rules() {
+        throw new coding_exception('define_decode_rules() method needs to be overridden in each subclass of restore_block_task');
+    }
 
 // Protected API starts here
 
Index: lib/portfolio/plugin.php
===================================================================
--- lib/portfolio/plugin.php	(revision 1.24)
+++ lib/portfolio/plugin.php	(revision )
@@ -153,7 +153,9 @@
      *
      * @return string
      */
-    public static abstract function get_name();
+    public static function get_name() {
+        throw new coding_exception('get_name() method needs to be overridden in each subclass of portfolio_plugin_base');
+    }
 
     /**
     * check sanity of plugin
Index: backup/util/ui/base_ui.class.php
===================================================================
--- backup/util/ui/base_ui.class.php	(revision 1.2)
+++ backup/util/ui/base_ui.class.php	(revision )
@@ -212,7 +212,9 @@
      * Loads the backup controller if we are tracking one
      * @return backup_controller|false
      */
-    abstract public static function load_controller($uniqueid=false);
+    public static function load_controller($uniqueid=false) {
+        throw new coding_exception('load_controller() method needs to be overridden in each subclass of base_ui');
+    }
     /**
      * Gets an array of progress bar items that can be displayed through the backup renderer.
      * @return array Array of items for the progress bar
Index: lib/portfolio/formats.php
===================================================================
--- lib/portfolio/formats.php	(revision 1.14)
+++ lib/portfolio/formats.php	(revision )
@@ -39,14 +39,18 @@
     /**
      * array of mimetypes this format supports
      */
-    public static abstract function mimetypes();
+    public static function mimetypes() {
+        throw new coding_exception('mimetypes() method needs to be overridden in each subclass of portfolio_format');
+    }
 
     /**
      * for multipart formats, eg html with attachments,
      * we need to have a directory to place associated files in
      * inside the zip file. this is the name of that directory
      */
-    public static abstract function get_file_directory();
+    public static function get_file_directory() {
+        throw new coding_exception('get_file_directory() method needs to be overridden in each subclass of portfolio_format');
+    }
 
     /**
      * given a file, return a snippet of markup in whatever format
@@ -62,7 +66,9 @@
      *
      * @return string some html or xml or whatever
      */
-    public static abstract function file_output($file, $options=null);
+    public static function file_output($file, $options=null) {
+        throw new coding_exception('file_output() method needs to be overridden in each subclass of portfolio_format');
+    }
 
     public static function make_tag($file, $path, $attributes) {
         $srcattr = 'href';
Index: backup/moodle2/backup_block_task.class.php
===================================================================
--- backup/moodle2/backup_block_task.class.php	(revision 1.5)
+++ backup/moodle2/backup_block_task.class.php	(revision )
@@ -210,5 +210,7 @@
      * Code the transformations to perform in the block in
      * order to get transportable (encoded) links
      */
-    abstract static public function encode_content_links($content);
+    static public function encode_content_links($content) {
+        throw new coding_exception('encode_content_links() method needs to be overridden in each subclass of backup_block_task');
-}
+    }
+}
Index: backup/moodle2/backup_activity_task.class.php
===================================================================
--- backup/moodle2/backup_activity_task.class.php	(revision 1.8)
+++ backup/moodle2/backup_activity_task.class.php	(revision )
@@ -274,6 +274,8 @@
      * Code the transformations to perform in the activity in
      * order to get transportable (encoded) links
      */
-    abstract static public function encode_content_links($content);
+    static public function encode_content_links($content) {
+        throw new coding_exception('encode_content_links() method needs to be overridden in each subclass of backup_activity_task');
+    }
 
 }
Index: lib/portfolio/caller.php
===================================================================
--- lib/portfolio/caller.php	(revision 1.17)
+++ lib/portfolio/caller.php	(revision )
@@ -334,7 +334,9 @@
         return portfolio_most_specific_formats($specific, $basic);
     }
 
-    public abstract static function base_supported_formats();
+    public static function base_supported_formats() {
+        throw new coding_exception('base_supported_formats() method needs to be overridden in each subclass of portfolio_caller_base');
+    }
 
     /**
     * this is the "return to where you were" url
@@ -352,7 +354,9 @@
     /**
     * nice name to display to the user about this caller location
     */
-    public abstract static function display_name();
+    public static function display_name() {
+        throw new coding_exception('display_name() method needs to be overridden in each subclass of portfolio_caller_base');
+    }
 
     /**
     * return a string to put at the header summarising this export
@@ -475,7 +479,9 @@
      *
      * @return array
      */
-    public static abstract function expected_callbackargs();
+    public static function expected_callbackargs() {
+        throw new coding_exception('expected_callbackargs() method needs to be overridden in each subclass of portfolio_caller_base');
+    }
 
 
     /**