Description:
------------
When using Memcache::get for retrieving multiple entries, the keys of returned array may be broken, if key names contain some chars from 0x00 to 0x20. Everything is OK when using Memcache::get to retrieve single value.

Tested with PHP 5.4.9 and PHP 5.3.10 (version is irrelevant); php-memcache versions 3.0.6, 3.0.7 and 2.2.7; memcached 1.4.13.

Test script:
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<?php

$memcache = new Memcache();
$memcache->connect('localhost', '11211');

$prefix = 'TEST_';
$hex_key = '310e323334';
$key = $prefix . hex2bin($hex_key);

$value = 'test';

echo "Trying key: $prefix($hex_key)\n";

$set_result = $memcache->set($key, $value) !== false;
echo "set: " . ($set_result ? 'ok' : 'fail') . "\n";

$get_result_expected = $value;
$get_result = $memcache->get($key);
echo "get: " . (($get_result === $get_result_expected) ? 'ok' : 'fail') . ", '" . serialize($get_result) . "' vs '" . serialize($get_result_expected) . "'\n";

$multiget_result_expected = array($key => $value);
$multiget_result = $memcache->get(array($key));
echo "multiget: " . (($multiget_result === $multiget_result_expected) ? 'ok' : 'fail') . ", '" . serialize($multiget_result) . "' vs '" . serialize($multiget_result_expected) . "'\n";

echo "\n\n";


Expected result:
----------------
Trying key: TEST_(310e323334)
set: ok
get: ok, 's:4:"test";' vs 's:4:"test";'
multiget: fail, 'a:1:{s:10:"TEST_1_234";s:4:"test";}' vs 'a:1:{s:10:"TEST_1234";s:4:"test";}'


Actual result:
--------------
Trying key: TEST_(310e323334)
set: ok
get: ok, 's:4:"test";' vs 's:4:"test";'
multiget: ok, 'a:1:{s:10:"TEST_1?234";s:4:"test";}' vs 'a:1:{s:10:"TEST_1?234";s:4:"test";}'

(note: the "?" mark represents non-printable char)