diff -Naur -b participants_orig/blocks/participants/ReadMe.txt participants_mod/blocks/participants/ReadMe.txt
--- participants_orig/blocks/participants/ReadMe.txt	1970-01-01 01:00:00.000000000 +0100
+++ participants_mod/blocks/participants/ReadMe.txt	2009-06-11 09:00:22.000000000 +0100
@@ -0,0 +1,5 @@
+To get the block to show different icons for different roles, create an icon in the i directory of the theme being used and call it roleX.gif, where X is the roleid.
+
+e.g. Where Teachers are role 3 and the theme flashywhizzy is being used, which has custom icons, the path would be moodle/theme/flashywhizzy/pix/i/role3.gif
+
+Where custom icons aren't used, you'll need to add it to /moodle/pix/i
\ No newline at end of file
diff -Naur -b participants_orig/blocks/participants/block_participants.php participants_mod/blocks/participants/block_participants.php
--- participants_orig/blocks/participants/block_participants.php	2008-03-03 20:10:00.000000000 +0000
+++ participants_mod/blocks/participants/block_participants.php	2009-06-11 09:00:22.000000000 +0100
@@ -1,11 +1,13 @@
-<?PHP //$Id: block_participants.php,v 1.33.2.2 2008/03/03 11:41:03 moodler Exp $
+<?PHP //$Id: block_participants.php,v 1.35 2008/03/03 11:43:34 moodler Exp $
 
 class block_participants extends block_list {
     function init() {
         $this->title = get_string('people');
-        $this->version = 2007101509;
+        $this->version = 2009050810;
     }
 
+    function has_config() {return true;}
+
     function get_content() {
 
         global $CFG, $COURSE;
@@ -43,9 +45,40 @@
             }
         }
 
+        if ($CFG->block_participants_useroles == 1 && $CFG->block_participants_rolestouse != '') {
+            // Use the option to select the roles to show
+            $rolestoshow = $CFG->block_participants_rolestouse.',';
+            $roles = array();
+            if ($allroles = get_all_roles()) {
+                foreach ($allroles as $role) {
+                    $rolename = strip_tags(format_string($role->name, true));
+                    if (substr($rolename, -1, 1) != 's') {
+                        // Pluralise any roles that don't already end with an s
+                        // It's a bit of a bodge until someone suggests a more reliable method
+                        $rolename .= 's';
+                    }
+                    $roletofind = $role->id.',';
+                    if (strpos($rolestoshow, $roletofind) !== false) {
+                        $roles[$role->id] = $rolename;
+                        $this->content->items[] = '<a title="'.get_string('listofallpeople').'" href="'.
+                                      $CFG->wwwroot.'/user/index.php?contextid='.$currentcontext->id.'&roleid='.$role->id.'">'.$rolename.'</a>';
+
+                        // Check for the existance of an icon with the name roleX.gif, where X is the roleid
+                        if(file_exists($CFG->dirroot.'/theme/'.$CFG->theme.'/pix/i/role'.$role->id.'.gif')) {
+                            $this->content->icons[] = '<img src="'.$CFG->pixpath.'/i/role'.$role->id.'.gif" class="icon" alt="" />';
+                        } else {
+                            // If it can't be found, use the default icon
+                            $this->content->icons[] = '<img src="'.$CFG->pixpath.'/i/users.gif" class="icon" alt="" />';
+                        }
+                    }
+                }
+            }
+        } else {
+           // Use the default items to show
         $this->content->items[] = '<a title="'.get_string('listofallpeople').'" href="'.
                                   $CFG->wwwroot.'/user/index.php?contextid='.$currentcontext->id.'">'.get_string('participants').'</a>';
         $this->content->icons[] = '<img src="'.$CFG->pixpath.'/i/users.gif" class="icon" alt="" />';
+        }
 
         return $this->content;
     }
diff -Naur -b participants_orig/blocks/participants/settings.php participants_mod/blocks/participants/settings.php
--- participants_orig/blocks/participants/settings.php	1970-01-01 01:00:00.000000000 +0100
+++ participants_mod/blocks/participants/settings.php	2009-06-11 09:00:22.000000000 +0100
@@ -0,0 +1,22 @@
+<?php
+
+require_once $CFG->libdir.'/dmllib.php';
+
+$settings->add(new admin_setting_configcheckbox('block_participants_useroles', get_string('useroles', 'block_participants'),
+                   get_string('configuseroles', 'block_participants'), 0));
+
+// Get a list of non-guest roles
+$nonguestroles = array();
+if ($roles = get_all_roles()) {
+    foreach ($roles as $role) {
+        $rolename = strip_tags(format_string($role->name, true));
+        if (!isset($guestroles[$role->id])) {
+            $nonguestroles[$role->id] = $rolename;
+        }
+    }
+}
+
+$settings->add(new admin_setting_configmultiselect('block_participants_rolestouse', get_string('useroles', 'block_participants'),
+                      get_string('configuseroles', 'block_participants'), array(), $nonguestroles));
+
+?>
\ No newline at end of file
diff -Naur -b participants_orig/lang/en_utf8/block_participants.php participants_mod/lang/en_utf8/block_participants.php
--- participants_orig/lang/en_utf8/block_participants.php	1970-01-01 01:00:00.000000000 +0100
+++ participants_mod/lang/en_utf8/block_participants.php	2009-06-11 09:00:22.000000000 +0100
@@ -0,0 +1,8 @@
+<?PHP // $Id: block_online_users.php,v 1.2.8.2 2008/11/30 15:43:28 skodak Exp $ 
+      // block_online_users.php - created with Moodle 1.7 beta + (2006101003)
+
+
+$string['useroles'] = 'Select roles to appear';
+$string['configuseroles'] = 'Use this option to choose which roles to provide a link for in the block';
+
+?>