Description:
------------
I have followed the PHP documention in order to setup my memcached server cluster in my PHP application according to the instructions. When a server is being added which obviously shoudlnt work, the failurecallback-function is never being thrown.

Memcache PECL version2.2. @ $Revision: 1.114 $ is used. 

Reproduce code:
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function failureCallback($host, $port) {
    print "memcache '$host:$port' failed";
}
    
    $this->memcache = new Memcache;
    
    $this->memcache->addServer('Offlineserver', '11211', FALSE, 50, 10, 10, TRUE, 'failureCallback' );

Expected result:
----------------
Memcache Offlineserver:11211 failed

Actual result:
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Nothing happens