diff --git a/model/MongoStatement.php b/model/MongoStatement.php
index 1e86908..6097c10 100644
--- a/model/MongoStatement.php
+++ b/model/MongoStatement.php
@@ -60,11 +60,10 @@ class MongoStatement extends DbStatement
         if (!$this->result) {
             return false;
         }
-        if (isset($this->result['retval'])) {
+        if (is_array($this->result) && isset($this->result['retval'])) {
             return $this->result['retval'];
         }
 
-        $row = false;
         switch ($style) {
             case Db::FETCH_OBJ:
                 $row = $this->fetchObject();
diff --git a/tests/model/MongoDbCommandTest.php b/tests/model/MongoDbCommandTest.php
index 69fe5b5..c8d01fd 100644
--- a/tests/model/MongoDbCommandTest.php
+++ b/tests/model/MongoDbCommandTest.php
@@ -329,23 +329,23 @@ class MongoDbCommandTest extends PHPUnit_Framework_TestCase
     {
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::COUNT, new CollectionMock());
         $cmd->bindParam('condition', array());
-        $this->assertStringStartsWith('Collection: CollectionMock', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: CollectionMock', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::FIND, new CollectionMock());
         $cmd->bindParam('condition', array());
-        $this->assertStringStartsWith('Collection: CollectionMock', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: CollectionMock', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::COMMAND, new CollectionMock());
         $this->assertSame('Command properties not set', $cmd->__toString());
         $cmd->bindParam('command', array());
-        $this->assertStringStartsWith('Collection: CollectionMock', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: CollectionMock', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::INSERT, $this->collection);
         $this->assertSame('Command properties not set', $cmd->__toString());
         $cmd
                 ->bindParam('data', array('name' => 'insert'))
                 ->bindParam('safe', true);
-        $this->assertStringStartsWith('Collection: ', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: ', $cmd->__toString());
         $this->assertContains('Bulk insert: FALSE', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::INSERT, $this->collection);
@@ -357,14 +357,14 @@ class MongoDbCommandTest extends PHPUnit_Framework_TestCase
         $this->assertContains('Bulk insert: TRUE', $cmd->__toString());
 
         $cmd->bindParam('condition', array('name' => 'insert'))->bindParam('fields', array());
-        $this->assertStringStartsWith('Collection: ', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: ', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::REMOVE, $this->collection);
         $this->assertSame('Command properties not set', $cmd->__toString());
         $cmd
                 ->bindParam('condition', array('name' => 'insert'))
                 ->bindParam('safe', true);
-        $this->assertStringStartsWith('Collection: ', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: ', $cmd->__toString());
 
         $cmd = MongoCommandBuilder::factory(MongoCommandBuilder::UPDATE, $this->collection);
         $this->assertSame('Command properties not set', $cmd->__toString());
@@ -373,7 +373,7 @@ class MongoDbCommandTest extends PHPUnit_Framework_TestCase
                 ->bindParam('data', array('$set' => array('name' => 'update')))
                 ->bindParam('upsert', false)
                 ->bindParam('safe', true);
-        $this->assertStringStartsWith('Collection: ', $cmd->__toString());
+        $this->assertStringStartsWith("\n" . 'Collection: ', $cmd->__toString());
     }
 }
 
diff --git a/tests/model/MongoDriverTest.php b/tests/model/MongoDriverTest.php
index 4e4d3dd..e11bb2a 100644
--- a/tests/model/MongoDriverTest.php
+++ b/tests/model/MongoDriverTest.php
@@ -369,6 +369,24 @@ class MongoDriverTest extends PHPUnit_Framework_TestCase
      * @runInSeparateProcess
      * @group Mongo
      */
+    public function testEval()
+    {
+        if (!defined('DEBUG')) {
+            define('DEBUG', false);
+        }
+        $mongo = new MongoDriver($this->conf);
+        $result = $mongo->command('items', array('$eval' => 'function() {return true; }'));
+        $this->assertTrue($result->fetch());
+        $result = $mongo->command('items', array('$eval' => 'function() {return "Hello"; }'));
+        $this->assertSame('Hello', $result->fetch());
+        $result = $mongo->command('items', array('$eval' => 'function() {return db.items.count(); }'));
+        $this->assertEquals(5, $result->fetch());
+    }
+
+    /**
+     * @runInSeparateProcess
+     * @group Mongo
+     */
     public function testCommand()
     {
         if (!defined('DEBUG')) {