diff --git a/lib/Doctrine/Connection/Mysql.php b/lib/Doctrine/Connection/Mysql.php
index 9c219c618..df7aff261 100644
--- a/lib/Doctrine/Connection/Mysql.php
+++ b/lib/Doctrine/Connection/Mysql.php
@@ -40,7 +40,7 @@ class Doctrine_Connection_Mysql extends Doctrine_Connection_Common {
      * the constructor
      *
      * @param Doctrine_Manager $manager
-     * @param PDO $pdo                          database handle
+     * @param PDO|Doctrine_Adapter $adapter     database handler
      */
     public function __construct(Doctrine_Manager $manager, $adapter) {
         $adapter->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
@@ -68,6 +68,145 @@ class Doctrine_Connection_Mysql extends Doctrine_Connection_Common {
 
         parent::__construct($manager, $adapter);
     }    
+    /**
+     * Returns the next free id of a sequence
+     *
+     * @param string $seq_name name of the sequence
+     * @param boolean $ondemand when true the sequence is
+     *                          automatic created, if it
+     *                          not exists
+     *
+     * TODO: on demand creation of sequence table
+     *
+     * @return integer
+     */
+    public function nextID($seqName, $ondemand = true) {
+        $sequenceName = $this->quoteIdentifier($this->getSequenceName($seqName), true);
+        $seqcolName   = $this->quoteIdentifier($this->getAttribute(Doctrine::ATTR_SEQCOL_NAME), true);
+        $query        = 'INSERT INTO ' . $sequenceName . ' (' . $seqcolName . ') VALUES (NULL)';
+
+        $value = $this->dbh->lastInsertId();
+
+        if(is_numeric($value)) {
+            $query  = 'DELETE FROM ' . $sequenceName . ' WHERE ' . $seqcolName . ' < ' . $value;
+            $result = $this->dbh->query($query);
+        }
+        return $value;
+    }
+    /**
+     * Returns the current id of a sequence
+     *
+     * @param string $seq_name name of the sequence
+     * @return integer
+     */
+    public function currID($seqName) {
+        $sequenceName = $this->quoteIdentifier($this->getSequenceName($seqName), true);
+        $seqcolName = $this->quoteIdentifier($this->options['seqcol_name'], true);
+        $query = 'SELECT MAX(' . $seqcolName . ') FROM ' . $sequenceName;
+        return $this->queryOne($query, 'integer');
+    }
+    /**
+     * Execute a SQL REPLACE query. A REPLACE query is identical to a INSERT
+     * query, except that if there is already a row in the table with the same
+     * key field values, the REPLACE query just updates its values instead of
+     * inserting a new row.
+     *
+     * The REPLACE type of query does not make part of the SQL standards. Since
+     * practically only MySQL implements it natively, this type of query is
+     * emulated through this method for other DBMS using standard types of
+     * queries inside a transaction to assure the atomicity of the operation.
+     *
+     * @access public
+     *
+     * @param string $table name of the table on which the REPLACE query will
+     *  be executed.
+     * @param array $fields associative array that describes the fields and the
+     *  values that will be inserted or updated in the specified table. The
+     *  indexes of the array are the names of all the fields of the table. The
+     *  values of the array are also associative arrays that describe the
+     *  values and other properties of the table fields.
+     *
+     *  Here follows a list of field properties that need to be specified:
+     *
+     *    value:
+     *          Value to be assigned to the specified field. This value may be
+     *          of specified in database independent type format as this
+     *          function can perform the necessary datatype conversions.
+     *
+     *    Default:
+     *          this property is required unless the Null property
+     *          is set to 1.
+     *
+     *    type
+     *          Name of the type of the field. Currently, all types Metabase
+     *          are supported except for clob and blob.
+     *
+     *    Default: no type conversion
+     *
+     *    null
+     *          Boolean property that indicates that the value for this field
+     *          should be set to null.
+     *
+     *          The default value for fields missing in INSERT queries may be
+     *          specified the definition of a table. Often, the default value
+     *          is already null, but since the REPLACE may be emulated using
+     *          an UPDATE query, make sure that all fields of the table are
+     *          listed in this function argument array.
+     *
+     *    Default: 0
+     *
+     *    key
+     *          Boolean property that indicates that this field should be
+     *          handled as a primary key or at least as part of the compound
+     *          unique index of the table that will determine the row that will
+     *          updated if it exists or inserted a new row otherwise.
+     *
+     *          This function will fail if no key field is specified or if the
+     *          value of a key field is set to null because fields that are
+     *          part of unique index they may not be null.
+     *
+     *    Default: 0
+     *
+     * @return integer      the number of affected rows
+     */
+    public function replace($table, $fields) {
+        $count = count($fields);
+        $query = $values = '';
+        $keys = $colnum = 0;
+
+        for(reset($fields); $colnum < $count; next($fields), $colnum++) {
+            $name = key($fields);
+
+            if ($colnum > 0) {
+                $query .= ',';
+                $values.= ',';
+            }
+
+            $query .= $name;
+
+            if (isset($fields[$name]['null']) && $fields[$name]['null']) {
+                $value = 'NULL';
+            } else {
+                $type = isset($fields[$name]['type']) ? $fields[$name]['type'] : null;
+                $value = $this->quote($fields[$name]['value'], $type);
+            }
+
+            $values .= $value;
+
+            if (isset($fields[$name]['key']) && $fields[$name]['key']) {
+                if ($value === 'NULL')
+                    throw new Doctrine_Connection_Mysql_Exception('key value '.$name.' may not be NULL');
+
+                $keys++;
+            }
+        }
+
+        if ($keys == 0)
+            throw new Doctrine_Connection_Mysql_Exception('not specified which fields are keys');
 
 
+        $query = 'REPLACE INTO ' . $table . ' (' . $query . ') VALUES (' . $values . ')';
+
+        return $this->dbh->exec($query);
+    }
 }