As @Evan Mulawski notes, "2001" is interpreted as time, not year. Take out the comma so that PHP interprets "2001" as the year:
<?php $ts = strtotime("1 Nov 2001"); echo $ts . "\n"; $st = strftime("%B %d, %Y, %H:%M:%S", $ts); echo $st . "\n"; ?>
Output:
1004590800
November 01, 2001, 00:00:00
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