diff --git a/core/lib/Drupal/Core/Database/Connection.php b/core/lib/Drupal/Core/Database/Connection.php
index 51efaf4..5aa6c6f 100644
--- a/core/lib/Drupal/Core/Database/Connection.php
+++ b/core/lib/Drupal/Core/Database/Connection.php
@@ -134,6 +134,14 @@
    * @var array
    */
   protected $prefixReplace = array();
+  
+  /**
+   * The character set of this connection.
+   *
+   * @var string
+   */
+  protected $charset = 'utf8';
+  
 
   function __construct($dsn, $username, $password, $driver_options = array()) {
     // Initialize and prepare the connection prefix.
@@ -1172,4 +1180,17 @@ public function commit() {
    *   also larger than the $existing_id if one was passed in.
    */
   abstract public function nextId($existing_id = 0);
+    
+  /**
+   * Fetch the current character set for this connection.
+   *
+   * This is primarily important for handling 4-byte UTF8 in MySQL. See the 
+   * documentation in sites/default/default.settings.php for more information.
+   * @return string
+   */
+  public function charset() {
+    return $this->charset;
+  }
 }
+
+
diff --git a/core/lib/Drupal/Core/Database/Database.php b/core/lib/Drupal/Core/Database/Database.php
index 25fe8fa..fb6518d 100644
--- a/core/lib/Drupal/Core/Database/Database.php
+++ b/core/lib/Drupal/Core/Database/Database.php
@@ -220,6 +220,7 @@
         if (empty($value['driver'])) {
           $database_info[$index][$target] = $database_info[$index][$target][mt_rand(0, count($database_info[$index][$target]) - 1)];
         }
+        $database_info[$index][$target]['index'] = $index;
 
         // Parse the prefix information.
         if (!isset($database_info[$index][$target]['prefix'])) {
diff --git a/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php b/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php
index c70603c..45519a7 100644
--- a/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php
+++ b/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php
@@ -36,15 +36,6 @@ class Connection extends DatabaseConnection {
    */
   protected $needsCleanup = FALSE;
 
-  /**
-   * The character set of this connection.
-   * 
-   * Either utf8 or utf8mb4, but this could be extended to other charsets.
-   *
-   * @var string
-   */
-  protected $charset = 'utf8';
-
   public function __construct(array $connection_options = array()) {
     // This driver defaults to transaction support, except if explicitly passed FALSE.
     $this->transactionSupport = !isset($connection_options['transactions']) || ($connection_options['transactions'] !== FALSE);
@@ -78,14 +69,30 @@ public function __construct(array $connection_options = array()) {
 
     parent::__construct($dsn, $connection_options['username'], $connection_options['password'], $connection_options['pdo']);
 
-    // Apply user-defined charset for this connection if set for utf8mb4 support
-    // (see sites/default/default.settings.php for more on utf8mb4 support).
-    if (isset($connection_options['charset'])) {
-      $this->charset = $connection_options['charset'];
+// Default to 'utf8', but allow user to change this to
+    //  - any user-defined charset if this is not the default connection 
+    //  - any allowed charset if this is the default connection
+    // See sites/default/default.settings.php for full documentation
+    // Ideally we would test here to see if the charset is supported, but since
+    // we don't have a connection yet, we can't test here. So we only test
+    // during install.
+    
+    $default_connection_charsets = array('utf8', 'utf8mb4', 'utf8mb3'); //utf8mb3 is an alias for utf8
+    if (isset($connection_options['charset']) && $connection_options['charset'] != 'utf8' ) {
+      if ($connection_options['index'] != 'default') {
+        $this->charset = $connection_options['charset'];
+      }
+      elseif (in_array($connection_options['charset'], $default_connection_charsets)) {
+        $this->charset = $connection_options['charset'];
+      }
+      else {
+        drupal_set_message(t('The default connnection charset must be "utf8", "utf8mb3" or "utf8mb4". Currently defined as: ' . $connection_options['charset'] . '. Reverting to "utf8". Please check your charset definition in settings.php'), 'warning');
+      }
     }
     else {
       $this->charset = 'utf8';
     }
+
     if (!empty($connection_options['collation'])) {
       $this->exec('SET NAMES ' . $this->charset . ' COLLATE ' . $connection_options['collation']);
     }
@@ -250,22 +257,8 @@ protected function popCommittableTransactions() {
       }
     }
   }
-
-  /**
-   * Fetch the current character set for this connection.
-   * 
-   * Drupal defaults to use 3-byte UTF-8 with MySQL, but as of MySQL 5.5.3 it is
-   * possible to use full 4-byte UTF-8 (utf8mb4). See the documentation in 
-   * sites/default/default.settings.php on how to change this setting.
-   * 
-   * @return string
-   */
-  public function charset() {
-    return $this->charset;
-  }
 }
 
-
 /**
  * @} End of "addtogroup database".
  */
diff --git a/core/lib/Drupal/Core/Database/Driver/mysql/Install/Tasks.php b/core/lib/Drupal/Core/Database/Driver/mysql/Install/Tasks.php
index 0f3085f..5b37c47 100644
--- a/core/lib/Drupal/Core/Database/Driver/mysql/Install/Tasks.php
+++ b/core/lib/Drupal/Core/Database/Driver/mysql/Install/Tasks.php
@@ -90,13 +90,13 @@ public function validateDatabaseSettings($database) {
     // Perform standard validation.
     $errors = parent::validateDatabaseSettings($database);
 
-    // If we are using utf8mb4 charset, make sure the database supports it.
-    if (isset($database['charset']) && $database['charset'] == 'utf8mb4') {
-      if (!db_query("SHOW CHARACTER SET WHERE Charset = 'utf8mb4'")->rowCount()) {
-        $errors['mysql_charset'] = st('Your database does not support the utf8mb4 character set');
+    // If we are using a custom charset, make sure the database supports it.
+    if (isset($database['charset']) && $database['charset'] != 'utf8') {
+      $supported = db_query("SHOW CHARACTER SET LIKE = '".$database['charset']."'")->rowCount();
+      if (!$supported) {
+        $errors['mysql_charset'] = st('Your database does not support the '.$database['charset'].' character set');
       }
     }
-
     return $errors;
   }
 }
diff --git a/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php b/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
index 01f07de..ebb5737 100644
--- a/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
+++ b/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
@@ -112,10 +112,13 @@ protected function createTableSql($name, $table) {
     $sql .= 'ENGINE = ' . $table['mysql_engine'] . ' DEFAULT CHARACTER SET ' . $table['mysql_character_set'];
     // By default, MySQL uses the default collation for new tables, which is
     // 'utf8_general_ci' for utf8. If an alternate collation has been set, it
-    // needs to be explicitly specified.
+    // needs to be explicitly specified for each column, but the default 
+    // collation still needs to be utf8_general_ci.
     // @see DatabaseConnection_mysql
+    // This comment and the statement below code below could be deleted as MySQL
+    // will default to the correct value. Just here until this patch gets sorted.
     if (!empty($info['collation'])) {
-      $sql .= ' COLLATE ' . $info['collation'];
+      $sql .= ' COLLATE ' . 'utf8_general_ci';
     }
 
     // Add table comment.
@@ -138,6 +141,9 @@ protected function createTableSql($name, $table) {
    *   The field specification, as per the schema data structure format.
    */
   protected function createFieldSql($name, $spec) {
+    
+    $info = $this->connection->getConnectionOptions();
+    
     $sql = "`" . $name . "` " . $spec['mysql_type'];
 
     if (in_array($spec['mysql_type'], array('VARCHAR', 'CHAR', 'TINYTEXT', 'MEDIUMTEXT', 'LONGTEXT', 'TEXT'))) {
@@ -158,8 +164,11 @@ protected function createFieldSql($name, $spec) {
 
     // If it's a text field, check to see if we should use utf8mb4 (4-byte UTF8)
     // as the character set.
-    if (in_array($spec['mysql_type'], array('TINYTEXT', 'MEDIUMTEXT', 'LONGTEXT', 'TEXT')) && Database::getConnection()->charset() == 'utf8mb4') {
-      $sql .= ' CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci';
+    // InnoDB indexes have a max of 767 bytes. This means we can't use 4-byte 
+    // charsets on VARCHAR because there are VARCHAR-based indexes of 255 chars.
+    if (in_array($spec['mysql_type'], array('TINYTEXT', 'MEDIUMTEXT', 'LONGTEXT', 'TEXT')) &&  Database::getConnection()->charset() == 'utf8mb4') {
+          //    isset($info['charset']) && $info['charset'] != 'utf8') {
+      $sql .= ' CHARACTER SET '.$info['charset'].' COLLATE ' . $info['collation'];
     }
 
     if (isset($spec['not null'])) {
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index 595ccf9..bfc4817 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -169,15 +169,33 @@
  * problems when trying to save data that contains high-order UTF8 characters,
  * such as math symbols and rarer languages. If you have MySQL 5.5.3+, you can
  * turn on support for 4-byte UTF8 characters in text fields by enabling the
- * utf8mb4 character set on all text columns. More information on utf8mb4 can be
- * found here:
+ * 'utf8mb4' character set on all text columns. More information on 'utf8mb4'
+ *  can be found here:
  * http://dev.mysql.com/doc/refman/5.5/en/charset-unicode-utf8mb4.html
- *
- * An example of using the utf8mb4 character set:
+ * 
+ * Note that if you change your character set, you must also change your 
+ * collation. The collation prefix must match the character set name. See:
+ * http://dev.mysql.com/doc/refman/5.5/en/charset-unicode-sets.html
+ * 
+ * Finally, it is possible to use 'utf8mb3' which is currently simply an alias of 
+ * 'utf8', but MySQL reserves the right at a future date to make 'utf8' default
+ * to a 4-byte character set at which point 'utf8mb3' would specifically 
+ * indicate the legacy 3-byte version.
+ * 
+ * On the default connection, Drupal only allows use of utf8, utf8mb4 and 
+ * utf8mb3. Other charsets are allowed on other connections at the users risk 
+ *
+ * An example of setting custom character sets on the default connection and on
+ * a connection to a legacy database with a Croation charset and collation:
  *
  * @code
  * $databases['default']['default'] = array(
- *   'charset' => 'utf8mb4'
+ *   'charset' => 'utf8mb4',
+ *   'collation' => 'utf8mb4_general_ci',
+ * );
+ * $databases['legacy-app']['default'] = array(
+ *   'charset' => 'cp1250',
+ *   'collation' => 'cp1250_croation_ci',
  * );
  * @endcode
  *