diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php
index 170053c4f5..f910611b76 100644
--- a/phpBB/includes/functions.php
+++ b/phpBB/includes/functions.php
@@ -458,7 +458,7 @@ function _hash_crypt_private($password, $setting, &$itoa64)
 	$output = '*';
 
 	// Check for correct hash
-	if (substr($setting, 0, 3) != '$H$')
+	if (substr($setting, 0, 3) != '$H$' && substr($setting, 0, 3) != '$P$')
 	{
 		return $output;
 	}
diff --git a/tests/security/hash_test.php b/tests/security/hash_test.php
new file mode 100644
index 0000000000..19a3822145
--- /dev/null
+++ b/tests/security/hash_test.php
@@ -0,0 +1,21 @@
+<?php
+/**
+*
+* @package testing
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+require_once dirname(__FILE__) . '/../../phpBB/includes/functions.php';
+
+class phpbb_security_hash_test extends phpbb_test_case
+{
+	public function test_check_hash_with_phpass()
+	{
+		$this->assertTrue(phpbb_check_hash('test', '$H$9isfrtKXWqrz8PvztXlL3.daw4U0zI1'));
+		$this->assertTrue(phpbb_check_hash('test', '$P$9isfrtKXWqrz8PvztXlL3.daw4U0zI1'));
+		$this->assertFalse(phpbb_check_hash('foo', '$H$9isfrtKXWqrz8PvztXlL3.daw4U0zI1'));
+	}
+}
+