date gets converted to 1969 while using the php date function

Question

Why do I get 1969 when I convert the following date to Y-m-d format.

$date1="01/02/2012";
echo date('Y-m-d',$date1);

NOTE: This is php4.

Answer 1

You need to convert the date string to a timestamp:

echo date('Y-m-d', strtotime($date1));