The problem is similar to var_dump(). var_dump() is fixed by Yasuo today but another one raised (see Bug#16065)
var_export() has to handle recursive dependencies better and the fatal error is not an option.
Here is the script:
<?php 
$a=array(); 
$a[]=&$a; 
var_export($a);
?>
and the ouput:
bash-2.04$ ../php export.php 
X-Powered-By: PHP/4.3.0-dev
Content-type: text/html

array (
  0 => 
  array (
    0 => 
    array (
      0 => 
      array (
PHP Fatal error:  Nesting level too deep - recursive dependency? in /usr/samba/users/andy/412dev/php4-200203140300/te/export.php on line 4
<br />
<b>Fatal error</b>:  Nesting level too deep - recursive dependency? in <b>/usr/samba/users/andy/412dev/php4-200203140300/te/export.php</b> on line <b>4</b><br />

 Possible fix is another parameter(string) with var_export()-ed variable name - this will fix if the array has element which is reference to the array but will not handle this :
<?php
$a=array(1,2); 
$a[]=&$a; 
$b=array(&$a,3,4);
var_export($a);
?>
that crashes with output :
array (
  0 => 1,
  1 => 2,
  2 => 
  array (
    0 => 1,
    1 => 2,
    2 => 
    array (
      0 => 1,
      1 => 2,
      2 => 
      array (
        0 => 1,
        1 => 2,
        2 => 
        array (
PHP Fatal error:  Nesting level too deep - recursive dependency? in /usr/samba/users/andy/412dev/php4-200203140300/te/export.php on line 6
<br />
<b>Fatal error</b>:  Nesting level too deep - recursive dependency? in <b>/usr/samba/users/andy/412dev/php4-200203140300/te/export.php</b> on line <b>6</b><br />