diff --git a/src/Symfony/Component/Form/AbstractRendererEngine.php b/src/Symfony/Component/Form/AbstractRendererEngine.php
index 8202cbf97b641..f0fa5fbe80359 100644
--- a/src/Symfony/Component/Form/AbstractRendererEngine.php
+++ b/src/Symfony/Component/Form/AbstractRendererEngine.php
@@ -171,7 +171,7 @@ private function loadResourceForBlockNameHierarchy($cacheKey, FormView $view, ar
             // The next two if statements contain slightly duplicated code. This is by intention
             // and tries to avoid execution of unnecessary checks in order to increase performance.
 
-            if (isset($this->resources[$cacheKey][$parentBlockName])) {
+            if (isset($this->resources[$cacheKey][$parentBlockName]) && $this->resources[$cacheKey][$parentBlockName] !== false) {
                 // It may happen that the parent block is already loaded, but its level is not.
                 // In this case, the parent block must have been loaded by loadResourceForBlock(),
                 // which does not check the hierarchy of the block. Subsequently the block must have
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php b/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
index d68337e3bc8c1..80089efd933b6 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
@@ -77,7 +77,10 @@ public function buildView(FormView $view, FormInterface $form, array $options)
 
         $blockPrefixes = array();
         for ($type = $form->getConfig()->getType(); null !== $type; $type = $type->getParent()) {
-            array_unshift($blockPrefixes, $type->getBlockPrefix());
+            $blockPrefix = $type->getBlockPrefix();
+            if (!in_array($blockPrefix, $blockPrefixes)) {
+                array_unshift($blockPrefixes, $blockPrefix);
+            }
         }
         $blockPrefixes[] = $uniqueBlockPrefix;
 
diff --git a/src/Symfony/Component/Form/Tests/FixtureTypeTest.php b/src/Symfony/Component/Form/Tests/FixtureTypeTest.php
new file mode 100644
index 0000000000000..b8ec8c97a362f
--- /dev/null
+++ b/src/Symfony/Component/Form/Tests/FixtureTypeTest.php
@@ -0,0 +1,40 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Form\Tests;
+
+class FixtureTypeTest extends \Symfony\Component\Form\Test\TypeTestCase
+{
+    /**
+     * @dataProvider provideTypeClassBlockPrefix
+     */
+    public function testUniqueBlockPrefixes($typeClass, $blockPrefixes)
+    {
+        $form = $this->factory->create($typeClass);
+        $view = $form->createView();
+        $this->assertEquals($view->vars['block_prefixes'], $blockPrefixes);
+    }
+
+    /**
+     * @return array
+     */
+    public function provideTypeClassBlockPrefix()
+    {
+        return array(
+            array(__NAMESPACE__.'\Fixtures\Foo', ['form','foo','_foo']),
+            array(__NAMESPACE__.'\Fixtures\Type', ['form', 'type', '_type']),
+            array(__NAMESPACE__.'\Fixtures\FooBarHTMLType',['form', 'foo_bar_html', '_foo_bar_html']),
+            array(__NAMESPACE__.'\Fixtures\Foo1Bar2Type', ['form', 'foo1_bar2', '_foo1_bar2']),
+            array(__NAMESPACE__.'\Fixtures\OtherType\Foo1Bar2Type', ['form', 'foo1_bar2', '_foo1_bar2']),
+            array(__NAMESPACE__.'\Fixtures\FBooType', ['form', 'f_boo', '_f_boo']),
+        );
+    }
+}
diff --git a/src/Symfony/Component/Form/Tests/Fixtures/OtherType/Foo1Bar2Type.php b/src/Symfony/Component/Form/Tests/Fixtures/OtherType/Foo1Bar2Type.php
new file mode 100644
index 0000000000000..f6717ae2e4d3b
--- /dev/null
+++ b/src/Symfony/Component/Form/Tests/Fixtures/OtherType/Foo1Bar2Type.php
@@ -0,0 +1,22 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Form\Tests\Fixtures\OtherType;
+
+use Symfony\Component\Form\AbstractType;
+
+class Foo1Bar2Type extends AbstractType
+{
+    public function getParent()
+    {
+        return 'Symfony\Component\Form\Tests\Fixtures\Foo1Bar2Type';
+    }
+}