Description:
------------
Calling strtotime("-1 month",$date)
when
$date = march 30th
returns March 1st instead of february 30th (which actually doesn't exist in 2004), I would assume this means it should return February 29th or something close.

Reproduce code:
---------------
<?php
$date = date("2004-03-30");

$previousMonth = date("Y-m-d",strtotime("-1 month",strtotime($date)));

echo $previousMonth;
?>

Expected result:
----------------
2004-02-??

?? could be anything between 01 and 29.


Actual result:
--------------
2004-03-01