diff --git a/program/lib/Roundcube/bootstrap.php b/program/lib/Roundcube/bootstrap.php
index 3fe1808c0..3e85f9936 100644
--- a/program/lib/Roundcube/bootstrap.php
+++ b/program/lib/Roundcube/bootstrap.php
@@ -425,6 +425,7 @@ if (!function_exists('idn_to_ascii'))
 function rcube_autoload($classname)
 {
     if (strpos($classname, 'rcube') === 0) {
+        $classname = preg_replace('/^rcube_(cache|db|session|spellchecker)_/', '\\1/', $classname);
         $classname = 'Roundcube/' . $classname;
     }
     else if (strpos($classname, 'html_') === 0 || $classname === 'html') {
diff --git a/program/lib/Roundcube/rcube_cache_apc.php b/program/lib/Roundcube/cache/apc.php
similarity index 100%
rename from program/lib/Roundcube/rcube_cache_apc.php
rename to program/lib/Roundcube/cache/apc.php
diff --git a/program/lib/Roundcube/rcube_cache_db.php b/program/lib/Roundcube/cache/db.php
similarity index 100%
rename from program/lib/Roundcube/rcube_cache_db.php
rename to program/lib/Roundcube/cache/db.php
diff --git a/program/lib/Roundcube/rcube_cache_memcache.php b/program/lib/Roundcube/cache/memcache.php
similarity index 100%
rename from program/lib/Roundcube/rcube_cache_memcache.php
rename to program/lib/Roundcube/cache/memcache.php
diff --git a/program/lib/Roundcube/rcube_cache_redis.php b/program/lib/Roundcube/cache/redis.php
similarity index 100%
rename from program/lib/Roundcube/rcube_cache_redis.php
rename to program/lib/Roundcube/cache/redis.php
diff --git a/program/lib/Roundcube/rcube_db_mssql.php b/program/lib/Roundcube/db/mssql.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_mssql.php
rename to program/lib/Roundcube/db/mssql.php
diff --git a/program/lib/Roundcube/rcube_db_mysql.php b/program/lib/Roundcube/db/mysql.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_mysql.php
rename to program/lib/Roundcube/db/mysql.php
diff --git a/program/lib/Roundcube/rcube_db_oracle.php b/program/lib/Roundcube/db/oracle.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_oracle.php
rename to program/lib/Roundcube/db/oracle.php
diff --git a/program/lib/Roundcube/rcube_db_pgsql.php b/program/lib/Roundcube/db/pgsql.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_pgsql.php
rename to program/lib/Roundcube/db/pgsql.php
diff --git a/program/lib/Roundcube/rcube_db_sqlite.php b/program/lib/Roundcube/db/sqlite.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_sqlite.php
rename to program/lib/Roundcube/db/sqlite.php
diff --git a/program/lib/Roundcube/rcube_db_sqlsrv.php b/program/lib/Roundcube/db/sqlsrv.php
similarity index 100%
rename from program/lib/Roundcube/rcube_db_sqlsrv.php
rename to program/lib/Roundcube/db/sqlsrv.php
diff --git a/program/lib/Roundcube/rcube_spellchecker.php b/program/lib/Roundcube/rcube_spellchecker.php
index a0c340fd7..578397612 100644
--- a/program/lib/Roundcube/rcube_spellchecker.php
+++ b/program/lib/Roundcube/rcube_spellchecker.php
@@ -55,7 +55,7 @@ class rcube_spellchecker
             'dictionary'  => $this->rc->config->get('spellcheck_dictionary'),
         );
 
-        $cls = 'rcube_spellcheck_' . $this->engine;
+        $cls = 'rcube_spellchecker_' . $this->engine;
         if (class_exists($cls)) {
             $this->backend = new $cls($this, $this->lang);
             $this->backend->options = $this->options;
diff --git a/program/lib/Roundcube/rcube_session_db.php b/program/lib/Roundcube/session/db.php
similarity index 100%
rename from program/lib/Roundcube/rcube_session_db.php
rename to program/lib/Roundcube/session/db.php
diff --git a/program/lib/Roundcube/rcube_session_memcache.php b/program/lib/Roundcube/session/memcache.php
similarity index 100%
rename from program/lib/Roundcube/rcube_session_memcache.php
rename to program/lib/Roundcube/session/memcache.php
diff --git a/program/lib/Roundcube/rcube_session_php.php b/program/lib/Roundcube/session/php.php
similarity index 100%
rename from program/lib/Roundcube/rcube_session_php.php
rename to program/lib/Roundcube/session/php.php
diff --git a/program/lib/Roundcube/rcube_session_redis.php b/program/lib/Roundcube/session/redis.php
similarity index 100%
rename from program/lib/Roundcube/rcube_session_redis.php
rename to program/lib/Roundcube/session/redis.php
diff --git a/program/lib/Roundcube/rcube_spellcheck_atd.php b/program/lib/Roundcube/spellchecker/atd.php
similarity index 95%
rename from program/lib/Roundcube/rcube_spellcheck_atd.php
rename to program/lib/Roundcube/spellchecker/atd.php
index fc5319ed8..c8e924355 100644
--- a/program/lib/Roundcube/rcube_spellcheck_atd.php
+++ b/program/lib/Roundcube/spellchecker/atd.php
@@ -24,7 +24,7 @@
  * @package    Framework
  * @subpackage Utils
  */
-class rcube_spellcheck_atd extends rcube_spellcheck_engine
+class rcube_spellchecker_atd extends rcube_spellchecker_engine
 {
     const SERVICE_HOST = 'service.afterthedeadline.com';
     const SERVICE_PORT = 80;
@@ -41,7 +41,7 @@ class rcube_spellcheck_atd extends rcube_spellcheck_engine
     /**
      * Return a list of languages supported by this backend
      *
-     * @see rcube_spellcheck_engine::languages()
+     * @see rcube_spellchecker_engine::languages()
      */
     function languages()
     {
@@ -53,7 +53,7 @@ class rcube_spellcheck_atd extends rcube_spellcheck_engine
     /**
      * Set content and check spelling
      *
-     * @see rcube_spellcheck_engine::check()
+     * @see rcube_spellchecker_engine::check()
      */
     function check($text)
     {
@@ -163,7 +163,7 @@ class rcube_spellcheck_atd extends rcube_spellcheck_engine
     /**
      * Returns suggestions for the specified word
      *
-     * @see rcube_spellcheck_engine::get_words()
+     * @see rcube_spellchecker_engine::get_words()
      */
     function get_suggestions($word)
     {
@@ -179,7 +179,7 @@ class rcube_spellcheck_atd extends rcube_spellcheck_engine
     /**
      * Returns misspelled words
      *
-     * @see rcube_spellcheck_engine::get_suggestions()
+     * @see rcube_spellchecker_engine::get_suggestions()
      */
     function get_words($text = null)
     {
diff --git a/program/lib/Roundcube/rcube_spellcheck_enchant.php b/program/lib/Roundcube/spellchecker/enchant.php
similarity index 94%
rename from program/lib/Roundcube/rcube_spellcheck_enchant.php
rename to program/lib/Roundcube/spellchecker/enchant.php
index b2a86db76..635915d1f 100644
--- a/program/lib/Roundcube/rcube_spellcheck_enchant.php
+++ b/program/lib/Roundcube/spellchecker/enchant.php
@@ -24,7 +24,7 @@
  * @package    Framework
  * @subpackage Utils
  */
-class rcube_spellcheck_enchant extends rcube_spellcheck_engine
+class rcube_spellchecker_enchant extends rcube_spellchecker_engine
 {
     private $enchant_broker;
     private $enchant_dictionary;
@@ -33,7 +33,7 @@ class rcube_spellcheck_enchant extends rcube_spellcheck_engine
     /**
      * Return a list of languages supported by this backend
      *
-     * @see rcube_spellcheck_engine::languages()
+     * @see rcube_spellchecker_engine::languages()
      */
     function languages()
     {
@@ -74,7 +74,7 @@ class rcube_spellcheck_enchant extends rcube_spellcheck_engine
     /**
      * Set content and check spelling
      *
-     * @see rcube_spellcheck_engine::check()
+     * @see rcube_spellchecker_engine::check()
      */
     function check($text)
     {
@@ -118,7 +118,7 @@ class rcube_spellcheck_enchant extends rcube_spellcheck_engine
     /**
      * Returns suggestions for the specified word
      *
-     * @see rcube_spellcheck_engine::get_words()
+     * @see rcube_spellchecker_engine::get_words()
      */
     function get_suggestions($word)
     {
@@ -139,7 +139,7 @@ class rcube_spellcheck_enchant extends rcube_spellcheck_engine
     /**
      * Returns misspelled words
      *
-     * @see rcube_spellcheck_engine::get_suggestions()
+     * @see rcube_spellchecker_engine::get_suggestions()
      */
     function get_words($text = null)
     {
diff --git a/program/lib/Roundcube/rcube_spellcheck_engine.php b/program/lib/Roundcube/spellchecker/engine.php
similarity index 98%
rename from program/lib/Roundcube/rcube_spellcheck_engine.php
rename to program/lib/Roundcube/spellchecker/engine.php
index d6135f9a0..3fc9f4371 100644
--- a/program/lib/Roundcube/rcube_spellcheck_engine.php
+++ b/program/lib/Roundcube/spellchecker/engine.php
@@ -24,7 +24,7 @@
  * @package    Framework
  * @subpackage Utils
  */
-abstract class rcube_spellcheck_engine
+abstract class rcube_spellchecker_engine
 {
     const MAX_SUGGESTIONS = 10;
 
diff --git a/program/lib/Roundcube/rcube_spellcheck_googie.php b/program/lib/Roundcube/spellchecker/googie.php
similarity index 95%
rename from program/lib/Roundcube/rcube_spellcheck_googie.php
rename to program/lib/Roundcube/spellchecker/googie.php
index 985ae89d2..a1387256b 100644
--- a/program/lib/Roundcube/rcube_spellcheck_googie.php
+++ b/program/lib/Roundcube/spellchecker/googie.php
@@ -24,7 +24,7 @@
  * @package    Framework
  * @subpackage Utils
  */
-class rcube_spellcheck_googie extends rcube_spellcheck_engine
+class rcube_spellchecker_googie extends rcube_spellchecker_engine
 {
     const GOOGIE_HOST = 'ssl://spell.roundcube.net';
     const GOOGIE_PORT = 443;
@@ -35,7 +35,7 @@ class rcube_spellcheck_googie extends rcube_spellcheck_engine
     /**
      * Return a list of languages supported by this backend
      *
-     * @see rcube_spellcheck_engine::languages()
+     * @see rcube_spellchecker_engine::languages()
      */
     function languages()
     {
@@ -50,7 +50,7 @@ class rcube_spellcheck_googie extends rcube_spellcheck_engine
     /**
      * Set content and check spelling
      *
-     * @see rcube_spellcheck_engine::check()
+     * @see rcube_spellchecker_engine::check()
      */
     function check($text)
     {
@@ -133,7 +133,7 @@ class rcube_spellcheck_googie extends rcube_spellcheck_engine
     /**
      * Returns suggestions for the specified word
      *
-     * @see rcube_spellcheck_engine::get_words()
+     * @see rcube_spellchecker_engine::get_words()
      */
     function get_suggestions($word)
     {
@@ -154,7 +154,7 @@ class rcube_spellcheck_googie extends rcube_spellcheck_engine
     /**
      * Returns misspelled words
      *
-     * @see rcube_spellcheck_engine::get_suggestions()
+     * @see rcube_spellchecker_engine::get_suggestions()
      */
     function get_words($text = null)
     {
diff --git a/program/lib/Roundcube/rcube_spellcheck_pspell.php b/program/lib/Roundcube/spellchecker/pspell.php
similarity index 94%
rename from program/lib/Roundcube/rcube_spellcheck_pspell.php
rename to program/lib/Roundcube/spellchecker/pspell.php
index f70517ae0..914a22309 100644
--- a/program/lib/Roundcube/rcube_spellcheck_pspell.php
+++ b/program/lib/Roundcube/spellchecker/pspell.php
@@ -24,7 +24,7 @@
  * @package    Framework
  * @subpackage Utils
  */
-class rcube_spellcheck_pspell extends rcube_spellcheck_engine
+class rcube_spellchecker_pspell extends rcube_spellchecker_engine
 {
     private $plink;
     private $matches = array();
@@ -32,7 +32,7 @@ class rcube_spellcheck_pspell extends rcube_spellcheck_engine
     /**
      * Return a list of languages supported by this backend
      *
-     * @see rcube_spellcheck_engine::languages()
+     * @see rcube_spellchecker_engine::languages()
      */
     function languages()
     {
@@ -80,7 +80,7 @@ class rcube_spellcheck_pspell extends rcube_spellcheck_engine
     /**
      * Set content and check spelling
      *
-     * @see rcube_spellcheck_engine::check()
+     * @see rcube_spellchecker_engine::check()
      */
     function check($text)
     {
@@ -124,7 +124,7 @@ class rcube_spellcheck_pspell extends rcube_spellcheck_engine
     /**
      * Returns suggestions for the specified word
      *
-     * @see rcube_spellcheck_engine::get_words()
+     * @see rcube_spellchecker_engine::get_words()
      */
     function get_suggestions($word)
     {
@@ -145,7 +145,7 @@ class rcube_spellcheck_pspell extends rcube_spellcheck_engine
     /**
      * Returns misspelled words
      *
-     * @see rcube_spellcheck_engine::get_suggestions()
+     * @see rcube_spellchecker_engine::get_suggestions()
      */
     function get_words($text = null)
     {
diff --git a/tests/Framework/SpellcheckAtd.php b/tests/Framework/SpellcheckAtd.php
deleted file mode 100644
index cc828240f..000000000
--- a/tests/Framework/SpellcheckAtd.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-/**
- * Test class to test rcube_spellcheck_atd class
- *
- * @package Tests
- */
-class Framework_SpellcheckAtd extends PHPUnit_Framework_TestCase
-{
-
-    /**
-     * Class constructor
-     */
-    function test_class()
-    {
-        $object = new rcube_spellcheck_atd(null, 'en');
-
-        $this->assertInstanceOf('rcube_spellcheck_atd', $object, "Class constructor");
-        $this->assertInstanceOf('rcube_spellcheck_engine', $object, "Class constructor");
-    }
-}
diff --git a/tests/Framework/SpellcheckEnchant.php b/tests/Framework/SpellcheckEnchant.php
deleted file mode 100644
index 85393e76c..000000000
--- a/tests/Framework/SpellcheckEnchant.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-/**
- * Test class to test rcube_spellcheck_enchant class
- *
- * @package Tests
- */
-class Framework_SpellcheckEnchant extends PHPUnit_Framework_TestCase
-{
-
-    /**
-     * Class constructor
-     */
-    function test_class()
-    {
-        $object = new rcube_spellcheck_enchant(null, 'en');
-
-        $this->assertInstanceOf('rcube_spellcheck_enchant', $object, "Class constructor");
-        $this->assertInstanceOf('rcube_spellcheck_engine', $object, "Class constructor");
-    }
-}
diff --git a/tests/Framework/SpellcheckGoogie.php b/tests/Framework/SpellcheckGoogie.php
deleted file mode 100644
index dc7d70dcc..000000000
--- a/tests/Framework/SpellcheckGoogie.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-/**
- * Test class to test rcube_spellcheck_googie class
- *
- * @package Tests
- */
-class Framework_SpellcheckGoogie extends PHPUnit_Framework_TestCase
-{
-
-    /**
-     * Class constructor
-     */
-    function test_class()
-    {
-        $object = new rcube_spellcheck_googie(null, 'en');
-
-        $this->assertInstanceOf('rcube_spellcheck_googie', $object, "Class constructor");
-        $this->assertInstanceOf('rcube_spellcheck_engine', $object, "Class constructor");
-    }
-}
diff --git a/tests/Framework/SpellcheckPspell.php b/tests/Framework/SpellcheckPspell.php
deleted file mode 100644
index bd622b206..000000000
--- a/tests/Framework/SpellcheckPspell.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-/**
- * Test class to test rcube_spellcheck_pspell class
- *
- * @package Tests
- */
-class Framework_SpellcheckPspell extends PHPUnit_Framework_TestCase
-{
-
-    /**
-     * Class constructor
-     */
-    function test_class()
-    {
-        $object = new rcube_spellcheck_pspell(null, 'en');
-
-        $this->assertInstanceOf('rcube_spellcheck_pspell', $object, "Class constructor");
-        $this->assertInstanceOf('rcube_spellcheck_engine', $object, "Class constructor");
-    }
-}
diff --git a/tests/Framework/SpellcheckerAtd.php b/tests/Framework/SpellcheckerAtd.php
new file mode 100644
index 000000000..d3152eaf3
--- /dev/null
+++ b/tests/Framework/SpellcheckerAtd.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Test class to test rcube_spellcheck_atd class
+ *
+ * @package Tests
+ */
+class Framework_SpellcheckerAtd extends PHPUnit_Framework_TestCase
+{
+
+    /**
+     * Class constructor
+     */
+    function test_class()
+    {
+        $object = new rcube_spellchecker_atd(null, 'en');
+
+        $this->assertInstanceOf('rcube_spellchecker_atd', $object, "Class constructor");
+        $this->assertInstanceOf('rcube_spellchecker_engine', $object, "Class constructor");
+    }
+}
diff --git a/tests/Framework/SpellcheckerEnchant.php b/tests/Framework/SpellcheckerEnchant.php
new file mode 100644
index 000000000..aad69d9db
--- /dev/null
+++ b/tests/Framework/SpellcheckerEnchant.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Test class to test rcube_spellcheck_enchant class
+ *
+ * @package Tests
+ */
+class Framework_SpellcheckerEnchant extends PHPUnit_Framework_TestCase
+{
+
+    /**
+     * Class constructor
+     */
+    function test_class()
+    {
+        $object = new rcube_spellchecker_enchant(null, 'en');
+
+        $this->assertInstanceOf('rcube_spellchecker_enchant', $object, "Class constructor");
+        $this->assertInstanceOf('rcube_spellchecker_engine', $object, "Class constructor");
+    }
+}
diff --git a/tests/Framework/SpellcheckerGoogie.php b/tests/Framework/SpellcheckerGoogie.php
new file mode 100644
index 000000000..f1713eb11
--- /dev/null
+++ b/tests/Framework/SpellcheckerGoogie.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Test class to test rcube_spellcheck_googie class
+ *
+ * @package Tests
+ */
+class Framework_SpellcheckerGoogie extends PHPUnit_Framework_TestCase
+{
+
+    /**
+     * Class constructor
+     */
+    function test_class()
+    {
+        $object = new rcube_spellchecker_googie(null, 'en');
+
+        $this->assertInstanceOf('rcube_spellchecker_googie', $object, "Class constructor");
+        $this->assertInstanceOf('rcube_spellchecker_engine', $object, "Class constructor");
+    }
+}
diff --git a/tests/Framework/SpellcheckerPspell.php b/tests/Framework/SpellcheckerPspell.php
new file mode 100644
index 000000000..5888a8c0a
--- /dev/null
+++ b/tests/Framework/SpellcheckerPspell.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Test class to test rcube_spellcheck_pspell class
+ *
+ * @package Tests
+ */
+class Framework_SpellcheckerPspell extends PHPUnit_Framework_TestCase
+{
+
+    /**
+     * Class constructor
+     */
+    function test_class()
+    {
+        $object = new rcube_spellchecker_pspell(null, 'en');
+
+        $this->assertInstanceOf('rcube_spellchecker_pspell', $object, "Class constructor");
+        $this->assertInstanceOf('rcube_spellchecker_engine', $object, "Class constructor");
+    }
+}