diff --git a/.idea/php.xml b/.idea/php.xml
index 94d346e..f72d448 100644
--- a/.idea/php.xml
+++ b/.idea/php.xml
@@ -81,7 +81,6 @@
       <path value="$PROJECT_DIR$/vendor/zendframework/zend-eventmanager" />
       <path value="$PROJECT_DIR$/vendor/zendframework/zend-code" />
       <path value="$PROJECT_DIR$/vendor/bin/.phpunit" />
-      <path value="$PROJECT_DIR$/vendor/oro/doctrine-extensions" />
     </include_path>
   </component>
   <component name="PhpProjectSharedConfiguration" php_language_level="7.1" />
diff --git a/DependencyInjection/Curiosity26AclHelperExtension.php b/DependencyInjection/Curiosity26AclHelperExtension.php
index b9e3b8d..e927059 100644
--- a/DependencyInjection/Curiosity26AclHelperExtension.php
+++ b/DependencyInjection/Curiosity26AclHelperExtension.php
@@ -8,12 +8,14 @@
 
 namespace Curiosity26\AclHelperBundle\DependencyInjection;
 
+use Curiosity26\AclHelperBundle\Doctrine\DQL\CastAsInt;
 use Symfony\Component\Config\FileLocator;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Extension\Extension;
+use Symfony\Component\DependencyInjection\Extension\PrependExtensionInterface;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
 
-class Curiosity26AclHelperExtension extends Extension
+class Curiosity26AclHelperExtension extends Extension implements PrependExtensionInterface
 {
     /**
      * @param array $configs
@@ -26,4 +28,19 @@ public function load(array $configs, ContainerBuilder $container)
         $loader = new YamlFileLoader($container, new FileLocator([__DIR__.'/../Resources/config/']));
         $loader->load('services.yaml');
     }
+
+    public function prepend(ContainerBuilder $container)
+    {
+        $configs = $container->getExtensionConfig('doctrine');
+
+        if (!empty($configs) && array_key_exists('orm', $configs[0])) {
+            $config                                                                         = $configs[0];
+            $default                                                                        = array_key_exists(
+                'default_entity_manager',
+                $config['orm']
+            ) ? $config['orm']['default_entity_manager'] : 'default';
+            $config['orm']['entity_managers'][$default]['dql']['string_functions']['INT'] = CastAsInt::class;
+            $container->prependExtensionConfig('doctrine', $config);
+        }
+    }
 }
diff --git a/Doctrine/DQL/CastAsInt.php b/Doctrine/DQL/CastAsInt.php
new file mode 100644
index 0000000..533e4df
--- /dev/null
+++ b/Doctrine/DQL/CastAsInt.php
@@ -0,0 +1,38 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: alex.boyce
+ * Date: 11/12/18
+ * Time: 3:34 PM
+ */
+
+namespace Curiosity26\AclHelperBundle\Doctrine\DQL;
+
+use Doctrine\ORM\Query\AST\Functions\FunctionNode;
+use Doctrine\ORM\Query\AST\InputParameter;
+use Doctrine\ORM\Query\Lexer;
+use Doctrine\ORM\Query\Parser;
+use Doctrine\ORM\Query\SqlWalker;
+
+class CastAsInt extends FunctionNode
+{
+    /**
+     * @var InputParameter
+     */
+    public $stringPrimary;
+
+    public function getSql(SqlWalker $sqlWalker)
+    {
+        return 'CAST(' . $this->stringPrimary->dispatch($sqlWalker) . ' AS integer)';
+    }
+
+    public function parse(Parser $parser)
+    {
+        $parser->match(Lexer::T_IDENTIFIER);
+        $parser->match(Lexer::T_OPEN_PARENTHESIS);
+
+        $this->stringPrimary = $parser->StringPrimary();
+
+        $parser->match(Lexer::T_CLOSE_PARENTHESIS);
+    }
+}
\ No newline at end of file
diff --git a/QueryBuilder/AclHelperQueryBuilder.php b/QueryBuilder/AclHelperQueryBuilder.php
index d1699e0..90b641c 100644
--- a/QueryBuilder/AclHelperQueryBuilder.php
+++ b/QueryBuilder/AclHelperQueryBuilder.php
@@ -104,7 +104,7 @@ public function buildAclQuery($strategy = PermissionGrantingStrategy::ANY)
         }
 
         $q
-            ->select('acl_o.objectIdentifier')
+            ->select('INT(acl_o.objectIdentifier)')
             ->distinct()
             ->from(ObjectIdentity::class, 'acl_o')
             ->innerJoin(AclClass::class, 'acl_c', Join::WITH, 'acl_c.id = acl_o.classId')