function days($s,$e) {
		$s = strtotime($s);
		$e = strtotime($e);
		
		$p = 24*60*60;
		
		for($i=$s;$i<$e;$i=$i+$p) {
			if(!$Days[date("l",$i)]) {
				$Days[date("l",$i)] = 1;
			} else {
				$Days[date("l",$i)]++;
			}
		}
		echo "<pre>";
		print_r($Days);
		echo "</pre>";
	}

days("2014-01-01","2014-02-01");

Array
(
    [Wednesday] => 5
    [Thursday] => 5
    [Friday] => 5
    [Saturday] => 4
    [Sunday] => 4
    [Monday] => 4
    [Tuesday] => 4
)