Blank Screen After Installation on Fedora 12

After successfully installing Zen Cart on my Fedora 12 Linux Box, I immediately got a blank screen when I tried either the main page or the admin page. After using the information found in the tutorial, "I am getting a blank page (or blank part of a page)", I realized that Zen Cart was defining the function
date_diff in both includes/functions/functions_general.php and in admin/includes/functions/general.php.

I fixed this problem by enclosing both definitions in a
if(!function_defined("date_diff")){
function date_diff($date1, $date2) {

    //$date1  today, or any other day

    //$date2  date to check against



   $d1 = explode("-", $date1);

   $y1 = $d1[0];

   $m1 = $d1[1];

   $d1 = $d1[2];



   $d2 = explode("-", $date2);

   $y2 = $d2[0];

   $m2 = $d2[1];

   $d2 = $d2[2];



   $date1_set = mktime(0,0,0, $m1, $d1, $y1);

   $date2_set = mktime(0,0,0, $m2, $d2, $y2);



   return(round(($date2_set-$date1_set)/(60*60*24)));

  }

}

You're using a version of PHP for which the version of Zen Cart you're using was not designed.
You'll need this PHP 5.3 patch: http://www.zen-cart.com/forum/showthread.php?t=140960

Hello,

It can be a memory limit issue as well..whats the memory limit set?