diff --git a/lib/configuration.php b/lib/configuration.php
index dca895b..458c646 100644
--- a/lib/configuration.php
+++ b/lib/configuration.php
@@ -90,7 +90,7 @@ class configuration
         if (is_readable($configFile))
         {
             $config = parse_ini_file($configFile, true);
-            foreach (array('main', 'model') as $section) {
+            foreach (array('main', 'model', 'model_options') as $section) {
                 if (!array_key_exists($section, $config)) {
                     throw new Exception(i18n::_('PrivateBin requires configuration section [%s] to be present in configuration file.', $section), 2);
                 }
@@ -110,7 +110,12 @@ class configuration
                 continue;
             }
             // provide different defaults for database model
-            elseif ($section == 'model_options' && $this->_configuration['model']['class'] == 'privatebin_db')
+            elseif (
+                $section == 'model_options' && in_array(
+                    $this->_configuration['model']['class'],
+                    array('privatebin_db', 'zerobin_db')
+                )
+            )
             {
                 $values = array(
                     'dsn' => 'sqlite:' . PATH . 'data/db.sq3',
@@ -180,6 +185,12 @@ class configuration
             }
         }
 
+        // support for old config file format, before the fork was renamed
+        $this->_configuration['model']['class'] = str_replace(
+            'zerobin_', 'privatebin_',
+            $this->_configuration['model']['class']
+        );
+
         // ensure a valid expire default key is set
         if (!array_key_exists($this->_configuration['expire']['default'], $this->_configuration['expire_options']))
         {
diff --git a/lib/model.php b/lib/model.php
index 973fef5..7ca6317 100644
--- a/lib/model.php
+++ b/lib/model.php
@@ -61,13 +61,8 @@ class model
     {
         if ($this->_store === null)
         {
-            // added option to support old config file format
-            $model = str_replace(
-                'zerobin_', 'privatebin_',
-                $this->_conf->getKey('class', 'model')
-            );
             $this->_store = forward_static_call(
-                array($model, 'getInstance'),
+                array($this->_conf->getKey('class', 'model'), 'getInstance'),
                 $this->_conf->getSection('model_options')
             );
         }
diff --git a/lib/privatebin/db.php b/lib/privatebin/db.php
index e6a840c..373919a 100644
--- a/lib/privatebin/db.php
+++ b/lib/privatebin/db.php
@@ -134,6 +134,12 @@ class privatebin_db extends privatebin_abstract
                     self::_upgradeDatabase($db_version);
                 }
             }
+            else
+            {
+                throw new Exception(
+                    'Missing configuration for key dsn, usr, pwd or opt in the section model_options, please check your configuration file', 6
+                );
+            }
         }
 
         return self::$_instance;
diff --git a/tst/configuration.php b/tst/configuration.php
index 90d1b71..ac5b85d 100644
--- a/tst/configuration.php
+++ b/tst/configuration.php
@@ -3,6 +3,8 @@ class configurationTest extends PHPUnit_Framework_TestCase
 {
     private $_options;
 
+    private $_minimalConfig;
+
     public function setUp()
     {
         /* Setup Routine */
@@ -10,6 +12,7 @@ class configurationTest extends PHPUnit_Framework_TestCase
         $this->_options = configuration::getDefaults();
         $this->_options['model_options']['dir'] = PATH . $this->_options['model_options']['dir'];
         $this->_options['traffic']['dir'] = PATH . $this->_options['traffic']['dir'];
+        $this->_minimalConfig = '[main]' . PHP_EOL . '[model]' . PHP_EOL . '[model_options]';
     }
 
     public function tearDown()
@@ -51,7 +54,7 @@ class configurationTest extends PHPUnit_Framework_TestCase
 
     public function testHandleMinimalConfigFile()
     {
-        file_put_contents(CONF, '[main]' . PHP_EOL . '[model]');
+        file_put_contents(CONF, $this->_minimalConfig);
         $conf = new configuration;
         $this->assertEquals($this->_options, $conf->get(), 'returns correct defaults on empty file');
     }
@@ -62,7 +65,7 @@ class configurationTest extends PHPUnit_Framework_TestCase
      */
     public function testHandleInvalidSection()
     {
-        file_put_contents(CONF, '[main]' . PHP_EOL . '[model]');
+        file_put_contents(CONF, $this->_minimalConfig);
         $conf = new configuration;
         $conf->getKey('foo', 'bar');
     }
@@ -73,14 +76,14 @@ class configurationTest extends PHPUnit_Framework_TestCase
      */
     public function testHandleInvalidKey()
     {
-        file_put_contents(CONF, '[main]' . PHP_EOL . '[model]');
+        file_put_contents(CONF, $this->_minimalConfig);
         $conf = new configuration;
         $conf->getKey('foo');
     }
 
     public function testHandleGetKey()
     {
-        file_put_contents(CONF, '[main]' . PHP_EOL . '[model]');
+        file_put_contents(CONF, $this->_minimalConfig);
         $conf = new configuration;
         $this->assertEquals($this->_options['main']['sizelimit'], $conf->getKey('sizelimit'), 'get default size');
     }
@@ -115,4 +118,18 @@ class configurationTest extends PHPUnit_Framework_TestCase
         $this->assertEquals($options, $conf->get(), 'not overriding "missing" subkeys');
     }
 
+    public function testHandlePreRenameConfig()
+    {
+        $options = $this->_options;
+        $options['model']['class'] = 'zerobin_data';
+        helper::createIniFile(CONF, $options);
+        $conf = new configuration;
+        $this->assertEquals('privatebin_data', $conf->getKey('class', 'model'), 'old data class gets renamed');
+
+        $options['model']['class'] = 'zerobin_db';
+        helper::createIniFile(CONF, $options);
+        $conf = new configuration;
+        $this->assertEquals('privatebin_db', $conf->getKey('class', 'model'), 'old db class gets renamed');
+    }
+
 }
diff --git a/tst/privatebin/db.php b/tst/privatebin/db.php
index 6006723..a622bb1 100644
--- a/tst/privatebin/db.php
+++ b/tst/privatebin/db.php
@@ -139,6 +139,50 @@ class privatebin_dbTest extends PHPUnit_Framework_TestCase
         ));
     }
 
+    /**
+     * @expectedException Exception
+     * @expectedExceptionCode 6
+     */
+    public function testMissingDsn()
+    {
+        $options = $this->_options;
+        unset($options['dsn']);
+        privatebin_db::getInstance($options);
+    }
+
+    /**
+     * @expectedException Exception
+     * @expectedExceptionCode 6
+     */
+    public function testMissingUsr()
+    {
+        $options = $this->_options;
+        unset($options['usr']);
+        privatebin_db::getInstance($options);
+    }
+
+    /**
+     * @expectedException Exception
+     * @expectedExceptionCode 6
+     */
+    public function testMissingPwd()
+    {
+        $options = $this->_options;
+        unset($options['pwd']);
+        privatebin_db::getInstance($options);
+    }
+
+    /**
+     * @expectedException Exception
+     * @expectedExceptionCode 6
+     */
+    public function testMissingOpt()
+    {
+        $options = $this->_options;
+        unset($options['opt']);
+        privatebin_db::getInstance($options);
+    }
+
     public function testTableUpgrade()
     {
         $path = PATH . 'data/db-test.sq3';