Description:
------------
PHP: 5.3, 5.4
Unicode: not


Test script:
---------------
// 1. Works (output "<1>")
die(str_replace(
	array('{a1}', '{b1}', '{c1}', '{d1}'),
	array('a1', '', '1', 'd1'),
	'{b1} <{c1}>'
));

// 2. Error (output nothing)
die(str_replace(
	array('{a1}', '{b1}', '{c1}', '{d1}'),
	array('a1', '', 'c', 'd1'),
	'{b1} <{c1}>'
));

Expected result:
----------------
<c>

Actual result:
--------------
nothing