Index: signup.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/signup/signup.module,v
retrieving revision 1.205.2.19
diff -u -p -r1.205.2.19 signup.module
--- signup.module	3 Jun 2009 01:07:10 -0000	1.205.2.19
+++ signup.module	3 Jun 2009 18:10:06 -0000
@@ -1111,7 +1111,7 @@ function signup_content_types() {
  * $signup_form['signup_form_data'] : an array of key/value pairs --
  *   key is the data category, value is the user input
  */
-function signup_sign_up_user($signup_form) {
+function signup_sign_up_user($signup_form, $display_message = TRUE) {
   $node = node_load($signup_form['nid']);
 
   // Since this is an API call, we need to validate that there are no
@@ -1231,8 +1231,10 @@ function signup_sign_up_user($signup_for
       $language = user_preferred_language($signup);
       drupal_mail('signup', 'signup_forwarding_mail', $node->signup_forwarding_email, $language, $params, $from);
     }
-
-    drupal_set_message(t('Signup to !title confirmed.', array('!title' => l($node->title, "node/$node->nid"))) . $confirmation_email . $reminder_email);
+    if ($display_message) {
+      drupal_set_message(t('Signup to !title confirmed.', array('!title' => l($node->title, "node/$node->nid"))) . $confirmation_email . $reminder_email);
+    }
+    
 
     $node->signup_total++;
     if ($node->signup_close_signup_limit) {