Index: lib.php
===================================================================
RCS file: /cvsroot/moodle/moodle/mod/assignment/lib.php,v
retrieving revision 1.515.2.15
diff -u -r1.515.2.15 lib.php
--- lib.php	15 Mar 2012 12:00:05 -0000	1.515.2.15
+++ lib.php	23 Mar 2012 18:36:31 -0000
@@ -3363,13 +3363,16 @@
 function assignment_get_all_submissions($assignment, $sort="", $dir="DESC") {
 /// Return all assignment submissions by ENROLLED students (even empty)
     global $CFG, $DB;
-
+    $sortmethod=0;
     if ($sort == "lastname" or $sort == "firstname") {
-        $sort = "u.$sort $dir";
+        $sort = "$sort $dir";
+        $sortmethod =0;
     } else if (empty($sort)) {
-        $sort = "a.timemodified DESC";
+        $sort = "timemodified DESC";
+        $sortmethod=1;
     } else {
-        $sort = "a.$sort $dir";
+        $sort = "$sort $dir";
+        $sortmethod=1;
     }
 
     /* not sure this is needed at all since assignment already has a course define, so this join?
@@ -3378,12 +3381,27 @@
         $select = '';
     }*/
 
-    return $DB->get_records_sql("SELECT a.*
-                                   FROM {assignment_submissions} a, {user} u
-                                  WHERE u.id = a.userid
-                                        AND a.assignment = ?
-                               ORDER BY $sort", array($assignment->id));
-
+    $course = $DB->get_record("course", array("id"=>$assignment->course));
+    $userenrols= $DB->get_records_sql("SELECT ue.userid FROM {user_enrolments} ue , {enrol} e WHERE e.courseid=? AND ue.enrolid=e.id",array($course->id));
+    $i=0;
+    $userids =array();
+    foreach($userenrols as $userenrol){
+        $userids[$i]= $userenrol->userid;
+        $i++;
+    }   
+    
+    if($sortmethod!=0){
+        return $DB->get_records_list('assignment_submissions','userid',$userids,$sort);
+    }else{
+        $users = $DB->get_records_list("user","id",$userids,$sort);
+        $i=0;
+        $userids =array();
+        foreach($users as $user){
+            $userids[$i]= $user->id;
+            $i++;
+        }
+        return $DB->get_records_list('assignment_submissions','userid',$userids);
+    }
 }
 
 /**