Description:
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For some reason an attempt to save anything after storing a non-empty array with enough long key will fail.

After the failure, any operation with the value that failed to be stored will fail till I restart the memcache daemon.

Reproduce code:
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$memcache_obj = new Memcache;
$memcache_obj->connect('10.1.1.10', 11211);

$a = $memcache_obj->set('some_not_short_string',array('not_empty_array'));
$a = $memcache_obj->set('a',1);
var_dump($a);


Expected result:
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bool(true)

Actual result:
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bool(false)