Description:
------------
i'm using ob_start() with a callback function; internally in it i use $res=var_export($var, TRUE) function but got an error:
[11-Feb-2005 08:28:15] PHP Fatal error:  var_export() [<a href='ref.outcontrol'>ref.outcontrol</a>]: Cannot use output buffering in output buffering display handlers in E:\htdocs\index.php on line XXX

Reproduce code:
---------------
<?php
ob_start("my_shutdown_function");

function my_shutdown_function($buffer){
  $var=headers_list();
  $res=var_export($var, TRUE);
  return($res);
}

print("something...");
?>

Expected result:
----------------
the "dump" of all sent headers instead of string "something..."

Actual result:
--------------
"PHP Fatal error..."

Comment: this error actually must be when i call var_dump() or var_export($var, FALSE) in output buffering handler.