Index: moodle/group/clientlib.js
--- moodle/group/clientlib.js Base (1.1.2.2)
+++ moodle/group/clientlib.js Locally Modified (Based On 1.1.2.2)
@@ -161,12 +161,22 @@
         }
     }
     
+    var detailinfo = document.getElementById("detailinfo").value;
+    if (detailinfo == 0) {
+        detailinfo = 1;
+    } else {
+        detailinfo = 0;
+    }  
+    document.getElementById('detailinfo').value = detailinfo;
+   
     document.getElementById("showaddmembersform").disabled = !singleSelection;
+    document.getElementById("showmembersinfoform").disabled = !singleSelection;
     document.getElementById("showeditgroupsettingsform").disabled = !singleSelection;
     document.getElementById("deletegroup").disabled = selectionCount == 0;
 
     if(singleSelection) {
-        var sUrl = this.wwwRoot+"/group/index.php?id="+this.courseId+"&group="+groupId+"&act_ajax_getmembersingroup";
+        var sUrl = this.wwwRoot+"/group/index.php?id="+this.courseId+"&group="+groupId+"&act_ajax_getmembersingroup"+"&detailinfo="+detailinfo;
         YAHOO.util.Connect.asyncRequest("GET", sUrl, this.connectCallback, null);
     }
 };

Index: moodle/group/index.php
--- moodle/group/index.php Base (1.37.2.5)
+++ moodle/group/index.php Locally Modified (Based On 1.37.2.5)
@@ -22,6 +22,7 @@
 $courseid = required_param('id', PARAM_INT);
 $groupid  = optional_param('group', false, PARAM_INT);
 $userid   = optional_param('user', false, PARAM_INT);
+$detailinfo   = optional_param('detailinfo', false, PARAM_INT);
 $action   = groups_param_action();
 // Support either single group= parameter, or array groups[]
 if ($groupid) {
@@ -73,7 +74,8 @@
 
     case 'ajax_getmembersingroup':
         $roles = array();
-        if ($groupmemberroles = groups_get_members_by_role($groupids[0],$courseid,'u.id,u.firstname,u.lastname')) {
+        $displaycontent = empty($detailinfo) ? 'u.id,u.firstname,u.lastname' : 'u.id,u.firstname,u.lastname,u.email';       
+        if ($groupmemberroles = groups_get_members_by_role($groupids[0],$courseid,$displaycontent)) {
             foreach($groupmemberroles as $roleid=>$roledata) {
                 $shortroledata=new StdClass;
                 $shortroledata->name=$roledata->name;
@@ -82,11 +84,15 @@
                     $shortmember=new StdClass;
                     $shortmember->id=$member->id;
                     $shortmember->name=fullname($member, true);
+                    if (($detailinfo)){                        
+                        $shortmember->name .= ', ' .$member->email;
+                    }
                     $shortroledata->users[]=$shortmember;
                 }
                 $roles[]=$shortroledata;
             }
         }

         echo json_encode($roles);
         die;  // Client side JavaScript takes it from here.
 
@@ -148,6 +154,7 @@
 if (ajaxenabled()) {
     // Some buttons are enabled if single group selected
     $showaddmembersform_disabled = $singlegroup ? '' : $disabled;
+    $showmembersinfoform_disabled = $singlegroup ? '' : $disabled;
     $showeditgroupsettingsform_disabled = $singlegroup ? '' : $disabled;
     $deletegroup_disabled = count($groupids)>0 ? '' : $disabled;
 } else {
@@ -155,6 +162,7 @@
     // which you can change without reloading the page, so it is not appropriate
     // to disable them if no group is selected.
     $showaddmembersform_disabled = '';
+    $showmembersinfoform_disabled = '';
     $showeditgroupsettingsform_disabled = '';
     $deletegroup_disabled = '';
 }
@@ -255,6 +263,13 @@
 
 echo '<p><input type="submit" ' . $showaddmembersform_disabled . ' name="act_showaddmembersform" '
         . 'id="showaddmembersform" value="' . get_string('adduserstogroup', 'group'). '" /></p>'."\n";
+
+echo '<p><input type="submit" ' . $showmembersinfoform_disabled . ' name="act_showmembersinfoform" '
+        . 'id="showmembersinfoform" value="' . get_string('displayhideusersdetail', 'group')
+        . '" onclick="membersCombo.refreshMembers(); return false;" '
+        . '" /></p>'."\n";
+
+echo '<input type="hidden" id="detailinfo" value="1" />';
 echo '</td>'."\n";
 echo '</tr>'."\n";
 echo '</table>'."\n";
Index: moodle/lang/en_utf8/group.php
--- moodle/lang/en_utf8/group.php Base (1.22.2.6)
+++ moodle/lang/en_utf8/group.php Locally Modified (Based On 1.22.2.6)
@@ -50,6 +50,7 @@
 
 $string['removeselectedusers'] = 'Remove selected users';
 $string['adduserstogroup'] = 'Add/remove users';  //'from group'
+$string['displayhideusersdetail'] = 'Display/hide users detail';  //'from group'

 $string['addgroupstogroupings'] = 'Add/remove groups';  //'from group'
 
 $string['groupingname'] = 'Grouping name';