diff --git a/.gitignore b/.gitignore
index 9ec2b1e..2d99c06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -39,3 +39,4 @@ php-5.5.*.xz
 /php-5.6.4-strip.tar.xz
 /php-5.6.5RC1-strip.tar.xz
 /php-5.6.5-strip.tar.xz
+/php-5.6.6RC1-strip.tar.xz
diff --git a/php-datetime.patch b/php-datetime.patch
new file mode 100644
index 0000000..5685ac4
--- /dev/null
+++ b/php-datetime.patch
@@ -0,0 +1,52 @@
+From f457487e163502480f74a70bf9272fd003fc1919 Mon Sep 17 00:00:00 2001
+From: Julien Pauli <jpauli@php.net>
+Date: Thu, 5 Feb 2015 10:01:26 +0100
+Subject: [PATCH] Revert "Fixed bug #55407 (Impossible to prototype
+ DateTime::createFromFormat)"
+
+This reverts commit 8e19705a93d785cd1ff8ba3a69699b00169fea47.
+---
+ ext/date/php_date.c          |  2 +-
+ ext/date/tests/bug55407.phpt | 17 -----------------
+ 2 files changed, 1 insertion(+), 18 deletions(-)
+ delete mode 100644 ext/date/tests/bug55407.phpt
+
+diff --git a/ext/date/php_date.c b/ext/date/php_date.c
+index 8a7aeae..f8571b9 100644
+--- a/ext/date/php_date.c
++++ b/ext/date/php_date.c
+@@ -163,7 +163,7 @@ ZEND_END_ARG_INFO()
+ ZEND_BEGIN_ARG_INFO_EX(arginfo_date_create_from_format, 0, 0, 2)
+ 	ZEND_ARG_INFO(0, format)
+ 	ZEND_ARG_INFO(0, time)
+-	ZEND_ARG_OBJ_INFO(0, object, DateTimeZone, 1)
++	ZEND_ARG_INFO(0, object)
+ ZEND_END_ARG_INFO()
+ 
+ ZEND_BEGIN_ARG_INFO_EX(arginfo_date_parse, 0, 0, 1)
+diff --git a/ext/date/tests/bug55407.phpt b/ext/date/tests/bug55407.phpt
+deleted file mode 100644
+index 00c3356..0000000
+--- a/ext/date/tests/bug55407.phpt
++++ /dev/null
+@@ -1,17 +0,0 @@
+---TEST--
+-Bug #55407 (Impossible to prototype DateTime::createFromFormat)
+---INI--
+-error_reporting=-1
+---FILE--
+-<?php namespace melt\core;
+-
+-class DateTime extends \DateTime {
+-    public static function createFromFormat($format, $time, DateTimeZone $timezone = null) {
+-        return new DateTime(parent::createFromFormat($format, $time, $timezone));
+-    }
+-}
+-
+-echo "DONE\n";
+-?>
+---EXPECTF--
+-DONE
+-- 
+2.1.4
+
diff --git a/php.spec b/php.spec
index 82f32f5..c885ccb 100644
--- a/php.spec
+++ b/php.spec
@@ -57,12 +57,12 @@
 %global db_devel  libdb-devel
 %endif
 
-#global rcver         RC1
+%global rcver         RC1
 
 Summary: PHP scripting language for creating dynamic web sites
 Name: php
-Version: 5.6.5
-Release: 2%{?dist}
+Version: 5.6.6
+Release: 0.1.RC1%{?dist}
 # All files licensed under PHP version 3.01, except
 # Zend is licensed under Zend
 # TSRM is licensed under BSD
@@ -113,6 +113,8 @@ Patch46: php-5.6.3-fixheader.patch
 Patch47: php-5.6.3-phpinfo.patch
 
 # Upstream fixes (100+)
+# BC break reverted for release, but after RC
+Patch100: php-datetime.patch
 
 # Security fixes (200+)
 
@@ -716,6 +718,7 @@ httpd -V  | grep -q 'threaded:.*yes' && exit 1
 %patch47 -p1 -b .phpinfo
 
 # upstream patches
+%patch100 -p1 -b .datetime
 
 # security patches
 
@@ -1473,6 +1476,9 @@ rm -f README.{Zeus,QNX,CVS-RULES}
 
 
 %changelog
+* Thu Feb  5 2015 Remi Collet <rcollet@redhat.com> 5.6.6-0.1.RC1
+- php 5.6.6RC1 for Koschei
+
 * Mon Jan 26 2015 David Tardon <dtardon@redhat.com> - 5.6.5-2
 - rebuild for ICU 54.1
 
diff --git a/sources b/sources
index 4d2f11d..991e4f0 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-0bb0becc5b22d5565fe11e755ea9ddf5  php-5.6.5-strip.tar.xz
+33c5616af2f548aacf875d61a6a9fd60  php-5.6.6RC1-strip.tar.xz