Description:
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The docs say:
  mixed unserialize ( string str [, string callback])
  Note: The callback parameter was added in PHP 4.2.0

But if I make a call with 2 parameters, I get this:
  Warning: Wrong parameter count for unserialize()...

The unserialize_callback_func directive using ini_set() does not do anything as I get _PHP_Inclomplete_Class-es everywhere.

I also tried it with a 4.3.1 Linux CGI but it's the same...

Is this feature really implemented?

Thanx.


Reproduce code:
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$x = unserialize('O:1:"a":1:{s:5:"value";s:3:"100";}', 'dynamic_loader');