Index: rsvp.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/rsvp/rsvp.module,v
retrieving revision 1.9
diff -u -r1.9 rsvp.module
--- rsvp.module	29 Nov 2005 23:29:50 -0000	1.9
+++ rsvp.module	9 Jun 2006 00:56:16 -0000
@@ -571,6 +571,23 @@
 
     case t('Reply') :
       db_query('UPDATE {rsvp_invite} SET response = \'%s\', invited = 1, received = 1 WHERE hash = \'%s\'', $edit['invite_reply'], $edit['hash']);
+
+      // Signup module integration; if user is a valid user, is confirming
+      // their attendance, and has not already signed up for this event, 
+      // sign them up for it.
+      if ($edit['invite_reply'] == 'yes' && module_exist('signup')) {
+        $rsvp = _rsvp_get_invite($edit['hash']);
+        if ($rsvp->uid) {
+          $signups = signup_list_user_signups($rsvp->uid);
+          if (!in_array($rsvp->nid, array_keys($signups))) {
+            $edit['uid'] = $rsvp->uid;
+            $edit['nid'] = $rsvp->nid;
+            $edit['signup_form_data'] = array();
+            signup_sign_up_user($edit);
+          }
+        }
+      }
+
       break;
   }