    <?php


    $ar = Array(
      "form1" => Array
      (
        "hash" => 'lFfKBKiCTG6vOQDa8c7n',
        "time" => '1401067044'
       ),
      "form5" => Array
      (
        "hash" => 'TTmLVODDEkI1NrRnAbfB',
        "time" => '1401063352'
       ),
      "form4" => Array
      (
        "hash" => 'XCVOvrGbhuqAZehBmwoD',
        "time" => '1401063352'
       )
    );

    $condition = '1401067044';
    $newArray = array_filter($ar, function($form) use ($condition) {
        if (!isset($form['time'])) {
          return true;
        }
        return $form['time'] != $condition;
    });

     var_export($newArray);