diff --git a/drupal/sites/default/boinc/modules/contrib/privatemsg/privatemsg.module b/drupal/sites/default/boinc/modules/contrib/privatemsg/privatemsg.module
index 55fb9eac95..3fd91e5097 100644
--- a/drupal/sites/default/boinc/modules/contrib/privatemsg/privatemsg.module
+++ b/drupal/sites/default/boinc/modules/contrib/privatemsg/privatemsg.module
@@ -896,8 +896,8 @@ function privatemsg_new(&$form_state, $recipients = array(), $subject = '', $thr
     $to_themed[$user->uid] = $myname;
   }
   if (!empty($to)) {
-    $recipients_string = implode(' ', $to);
-    $recipients_string .= ' ';
+    $recipients_string = implode(', ', $to);
+    $recipients_string .= ', ';
   }
   if (isset($form_state['values'])) {
     if (isset($form_state['values']['recipient'])) {
@@ -913,7 +913,6 @@ function privatemsg_new(&$form_state, $recipients = array(), $subject = '', $thr
   elseif (!$thread_id) {
     drupal_set_title(t('Write new message'));
   }
-
   $form = array();
   if (isset($form_state['privatemsg_preview'])) {
     $form['message_header'] = array(
@@ -936,7 +935,7 @@ function privatemsg_new(&$form_state, $recipients = array(), $subject = '', $thr
     $form['privatemsg']['recipient'] = array(
       '#type'               => 'textfield',
       '#title'              => t('To'),
-      '#description'        => t('Separate multiple names with a space. The number appearing in the suffix is the BOINC id. You can find a user\'s BOINC id on their user profile page.'),
+      '#description'        => t('Separate multiple names with a comma followed by one space. The number appearing in the suffix is the BOINC id. You can find a user\'s BOINC id on their user profile page.'),
       '#default_value'      => $recipients_string,
       '#required'           => TRUE,
       '#weight'             => -10,
@@ -1089,7 +1088,7 @@ function _privatemsg_load_thread_participants($thread_id) {
  */
 function _privatemsg_parse_userstring($input) {
   if (is_string($input)) {
-    $input = explode(' ', $input);
+    $input = explode(', ', $input);
   }
 
   // Start working through the input array.
@@ -1420,7 +1419,7 @@ function privatemsg_sql_deleted(&$fragments, $days) {
 function privatemsg_user_name_autocomplete($string) {
   $names = array();
   // 1: Parse $string and build list of valid user names.
-  $fragments = explode(' ', $string);
+  $fragments = explode(', ', $string);
   foreach ($fragments as $index => $name) {
     if ($name = trim($name)) {
       $names[$name] = $name;
@@ -1435,11 +1434,11 @@ function privatemsg_user_name_autocomplete($string) {
     db_set_active('boinc');
     $result = db_query_range($query['query'], $fragment, 0, 10);
     db_set_active('default');
-    $prefix = count($names) ? implode(' ', $names) . ' ' : '';
+    $prefix = count($names) ? implode(', ', $names) . ', ' : '';
     // 3: Build proper suggestions and print.
     while ($user = db_fetch_object($result)) {
       $myname = preg_replace("/ /", "\xc2\xa0", $user->name);
-      $matches[$prefix . $myname . "_" . $user->id . ' '] = htmlentities($myname) . '(' . $user->id . ')';
+      $matches[$prefix . $myname . "_" . $user->id . ', '] = htmlentities($myname) . ' (' . $user->id . ')';
     }
   }
   // convert to object to prevent drupal bug, see http://drupal.org/node/175361