date problem

Hi Folks, I am trying to get the day of month for a particular day of week (e.g. Tuesday) for the first, second, third, fourth week in a month. The code i have seems issues in March, but works e.g. in April: print date("d-m-Y H:i:s",strtotime('1 March 2011 Tuesday')); >> 01-03-2011 00:00:00 print date("d-m-Y H:i:s",strtotime('1 March 2011 first Tuesday')); >> 08-03-2011 00:00:00 While in April, I have print date("d-m-Y H:i:s",strtotime('1 April 2011 Tuesday')); >> 05-04-2011 00:00:00 print date("d-m-Y H:i:s",strtotime('1 April 2011 first Tuesday')); >> 05-04-2011 00:00:00 Could someone help whats wrong with the technique i am trying to find that day of month. Is there any better way ? Thanks -dani