As of writing this note (PHP 5.3.1) serialization of closure is not allowed.This means a code like the one below:<?php//Closure$bar3 = function($a) { return $a * 2;};wincache_ucache_set('foo3', $bar3);var_dump(wincache_ucache_get('foo3'));echo "<br>";?> Will throw exception:[11-Feb-2010 09:25:33] PHP Fatal error: Uncaught exception 'Exception' with message 'Serialization of 'Closure' is not allowed' in C:\inetpub\wwwroot\phptest\tests\ucache\wincache15.php:6Stack trace:#0 C:\inetpub\wwwroot\phptest\tests\ucache\wincache15.php(6): wincache_ucache_set('foo3', Object(Closure))#1 {main} thrown in C:\inetpub\wwwroot\phptest\tests\ucache\wincache15.php on line 6However one catch this exception like:<?php//Closure$bar3 = function($a) { return $a * 2;};try{ wincache_ucache_set('foo3', $bar3);}catch (Exception $e){ var_dump($e->getMessage());}var_dump(wincache_ucache_get('foo3'));echo "<br>";?> This will generate output as shown beloe:string(41) "Serialization of 'Closure' is not allowed" NULL