Description:
------------
cases length and value give the expected results, but when mixed in the case of length_and_value it gives unexpected results.

Sorry for posting more than 20 lines i don't have an open server to post it to.

Ben

Reproduce code:
---------------
<?php

$doesntwork = array(
'd1_b_000_000_0_b_000_001_0_b_000_001_0', 
'd1_b_000_000_0_b_000_001_0_b_001_001_0', 
'd1_b_000_000_0_b_000_001_0_b_000_002_0', 
'd1_b_000_000_0_b_000_001_0_b_001_002_0', 
'd1_b_000_000_0_b_000_001_0_b_001_003_0', 
'd1_b_000_000_0_b_000_001_0_b_000_004_0_b_000_000_0', 
'd1_b_000_000_0_b_000_001_0_b_000_004_0_b_000_001_0', 
'd1_b_000_000_0_b_000_001_0_b_000_004_0_b_000_002_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_000_001_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_001_0_b_000_000_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_001_0_b_000_001_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_001_0_b_000_002_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_000_002_0' ,
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_002_0_b_000_000_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_002_0_b_000_001_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_002_002_0_b_000_002_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_000_003_0', 
'd1_b_000_000_0_b_000_001_0_b_000_005_0_b_000_001_0_b_000_004_0'
);

function value($a, $b)
{
	if($a < $b)	return -1;
	else								return 1;
}

function length($a, $b)
{
	if(strlen($a) < strlen($b))	return -1;
	else								return 1;
}

function length_and_value($a, $b)
{
	if(strlen($a) < strlen($b) || $a < $b)	return -1;
	else								return 1;
}

if(is_array($doesntwork))
{
	foreach($doesntwork as $id) echo '<br>'.$id;
	echo '<hr>';

	usort($doesntwork, 'length');

	foreach($doesntwork as $id) echo '<br>'.$id;
	echo '<hr>';

	usort($doesntwork, 'value');

	foreach($doesntwork as $id) echo '<br>'.$id;
	echo '<hr>';

	usort($doesntwork, 'length_and_value');

	foreach($doesntwork as $id) echo '<br>'.$id;
	echo '<hr>';
}

?>