--- office_hours.elements.inc	2009-06-26 11:13:28.000000000 -0500
+++ office_hours.elementsNEW.inc	2009-06-26 11:10:59.000000000 -0500
@@ -100,8 +100,8 @@ function office_hours_select_process($el
     $hour =  _office_hours_mil_to_tf($element['#default_hours']);
     list($defhr, $defmin) = explode(":",$hour);
     if ($element['#hoursformat']) {
-      if ($defhr > 12) {
-        $defhr -= 12;
+      if ($defhr >= 12) {
+        $defhr -= ($defhr != 12) ? 12 : 0;
         $ampm = 'pm';
       }
       elseif ($defhr == 0) {