Hi there - I am receiving a time date error for php but I can't figure out where to go and fix it - here's what the error says:

PHP Error Message: WARNINGstrftime(): It is not safe to rely on the system\'s timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected \'America/New_York\' for \'-4.0/DST\' insteadError in line 73 of file C:\\xampp\\htdocs\\plugins\\editors\\jce\\libraries\\classes\\utils.php

When I open the file line 73 is in this section:

65 }
66 /**
67 * Format the date.
68 * @param int $date the unix datestamp
69 * @return string formated date.
70 */
71 function formatDate($date, $format="%d/%m/%Y, %H:%M")
72 {
73 return strftime($format, $date);
74 }
75 /**
76 * Get the modified date of a file
77 *
78 * @return Formatted modified date
79 * @param string $file Absolute path to file
80 */
81 function getDate($file)
82 {
83 return Utils::formatDate(@filemtime($file));
84 }

I already changed the time zone setting within my joomla/admin global configurations -I don't get what I am supposed to change...am I supposed to replace what's on line 73 or am I supposed to declare the time zone along with what's already there? Help? Thanks -