Description:
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strtotime should be able to add 1 day to a given timestamp using "+1 day", under php 5.0.4 it does, after upgrading to 5.1.1 it returns "12/31/1969"

Reproduce code:
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$date = "12/21/2005";
$stamp = strtotime($date);
$new_date = date('n/j/Y',strtotime("+ 1 day",$stamp));


echo "<br>Date: ".$date;
echo "<br>Date +1: ".$new_date;


Expected result:
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Date: 12/21/2005
Date +1: 12/22/2005

Actual result:
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Date: 12/21/2005
Date +1: 12/31/1969