Description:
------------
Function var_export appears to not handle -ve array indexes and outputs the unsigned value.

Sample below.

This is on a standard Linux hosted service.


Test script:
---------------
<?php
$stylecache = array ( 
-1 => array 
( 1 => array 
( 0 => array ( 'styleid' => '19', 'title' => 'vB4 efault Style', 'parentid' => '-1', 'displayorder' => '1', 'userselect' => '1',  ),  ), ),
 19 => array (
 2 =>  array (  0 =>   array (  'styleid' => '20',  'title' => 'APintermGreen1',  'parentid' => '19',  'displayorder' => '2',  'userselect' => '1',  ),  ),  
 ),
);

var_export($stylecache);
?>

Expected result:
----------------
$stylecache = array (
  -1 => 
  array (
    1 => 
    array (
      0 => 
      array (
        'styleid' => '19',
        'title' => 'vB4 Default Style',
        'parentid' => '-1',
        'displayorder' => '1',
        'userselect' => '1',
      ),
    ),
  ),
  19 => 
  array (
    2 => 
    array (
      0 => 
      array (
        'styleid' => '20',
        'title' => 'APintermGreen1',
        'parentid' => '19',
        'displayorder' => '2',
        'userselect' => '1',
      ),
    ),
  ),
);


Actual result:
--------------
$stylecache = array (
  4294967295 => 
  array (
    1 => 
    array (
      0 => 
      array (
        'styleid' => '19',
        'title' => 'vB4 Default Style',
        'parentid' => '-1',
        'displayorder' => '1',
        'userselect' => '1',
      ),
    ),
  ),
  19 => 
  array (
    2 => 
    array (
      0 => 
      array (
        'styleid' => '20',
        'title' => 'APintermGreen1',
        'parentid' => '19',
        'displayorder' => '2',
        'userselect' => '1',
      ),
    ),
  ),
);