Description:
------------
Next function is not returning a value when it should be. Tried code sample below on a linux and windows distro both running PHP 5.2.1 and received desired results. When tested on SunOS 5.10 and PHP 5.2.4 the undesired results appeared.

Reproduce code:
---------------
$array = array(
			'key1' => array(
				'sub1_key1',
				'sub1_key2',
				'sub1_key3',
				'sub1_key4',
			),
			
			'key2' => array(
				'sub2_key1',
				'sub2_key2',
				'sub2_key3',
				'sub2_key4',
			)
		);
		
		foreach($array as $key => $sub_array) {
			
			foreach($sub_array as $sub_val) {
				echo $sub_val;
				
				if(next($sub_array))
					echo ', ';
			}
			
			$next = next($array);
			if(is_array($next)) {
				echo '||||';
			}
		
			print_r($next);
		
		}

Expected result:
----------------
sub1_key1, sub1_key2, sub1_key3, sub1_key4||||Array
(
    [0] => sub2_key1
    [1] => sub2_key2
    [2] => sub2_key3
    [3] => sub2_key4
)
sub2_key1, sub2_key2, sub2_key3, sub2_key4

Actual result:
--------------
sub1_key1, sub1_key2, sub1_key3, sub1_key4sub2_key1, sub2_key2, sub2_key3, sub2_key4