Description:
------------
See reproduce code, error: Fatal error: Using $this when not in object context in /home/michiel/public_html/test.php(11) : regexp code on line 1

Reproduce code:
---------------
<?
class a
{
	var $a = array();

	function a()
	{
		$output = preg_replace(
				'!\{\s*([a-z0-9_]+)\s*\}!sie',
				"(in_array('\\1',\$this->a) ? '\'.\$p[\'\\1\'].\'' : '\'.\$r[\'\\1\'].\'')",
				"{a} b {c}");
	}
}
new a();
?>

Expected result:
----------------
Worked just fine in PHP4