note 53964 added to function.checkdnsrr

Fatal error: Call to undefined function: checkdnsrr() in c:\apache\htdocs\radlance\src\common.php on line 1261 how do I fix it? ---- Manual Page -- http://www.php.net/manual/en/function.checkdnsrr.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+53964 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes&reason=useless Delete: non-english -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes&reason=non-english Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+53964&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+53964&report=yes Search -- http://master.php.net/manage/user-notes.php