note 50187 added to function.date

Hello, I am having some problem with the date functions. For your information i am using PHP Version 4.2.3 which is compiled on a HP UX. I want to write a code which convers the string data 'YYWW' into 'YYMM' format. ex: '0430' -> '0407' since 30th week comes in 07 month it got translated into '0407'. I had posted about this problem on other forums but couldnt get much help there. The code which i got from other forum is: <?php $yearweek='0414'; $year=substr($yearweek,0,2); $week=substr($yearweek,2); $unixtime=mktime(0,0,0,1,(($week-1)*7),$year); echo date('ym',strtotime('last monday',$unixtime)); ?> The above code works good for 2004 year, but again when i change the value of $yearweek to '0510' i get the return value as '0502' where as it should have been '0503'. If the remove the '-1' in line 5 then for 2005 and rest years it works but for 2004 it doesnt. I thought this problem was because of the 2004 being leap year but i was wrong. I tried to make condition which checks for the year being leap year or not. But this too didnt helped me. I dont know how i can solve this problem and will be very glad if anyone can help me in this matter. Thanks. P.s: also, i am using PHP Version 4.2.3 running on HP UX ---- Manual Page -- http://www.php.net/manual/en/function.date.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+50187 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+50187&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+50187&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+50187&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+50187&report=yes&reason=useless Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+50187&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+50187&report=yes Search -- http://master.php.net/manage/user-notes.php