--- signup_pay.module	2008-05-21 06:22:49.000000000 +0930
+++ /projects/trellon/pcc/sites/all/modules/signup_pay/signup_pay.module	2008-06-01 17:16:48.000000000 +0930
@@ -625,8 +625,17 @@
       if ($node->signup_pay_enabled) {
         $default_rid = signup_pay_find_user_role($user);
         $pay_roles = signup_pay_get_node_pay_roles($form['nid']['#value']);
+        $amount = $pay_roles[$default_rid]['amount'];
+        
+        // Invoke all adjustment modules, allows for multiple adjustments
+        $hook = 'signup_pay_adjust';
+        foreach (module_implements($hook) as $module) {
+          $function = $module .'_'. $hook;
+          $amount = call_user_func_array($function, array($node, $user, $amount));
+        }
+        
         $form['collapse']['signup_user_form']['payment'] = array(
-          '#value' => t('<div>The price you pay: %amount</div>', array('%amount' => _signup_pay_format_amount($pay_roles[$default_rid]['amount'],$pay_roles[$default_rid]['currency']))),
+          '#value' => t('<div>The price you pay: %amount</div>', array('%amount' => _signup_pay_format_amount($amount,$pay_roles[$default_rid]['currency']))),
         );
         $form['collapse']['signup_user_form']['method'] = array(
           '#type'          => 'radios',
@@ -811,6 +820,13 @@
   $amount = $pay_roles[$signup_rid]['amount'] ? $pay_roles[$signup_rid]['amount'] : variable_get(SIGNUP_PAY_AMOUNT, SIGNUP_PAY_DEFAULT_AMOUNT);
   $currency = $pay_roles[$signup_rid]['currency'] ? $pay_roles[$signup_rid]['currency'] : variable_get(SIGNUP_PAY_CURRENCY, SIGNUP_PAY_DEFAULT_CURRENCY);
 
+  // Invoke all adjustment modules, allows for multiple adjustments
+  $hook = 'signup_pay_adjust';
+  foreach (module_implements($hook) as $module) {
+    $function = $module .'_'. $hook;
+    $amount = call_user_func_array($function, array($node, $user, $amount));
+  }
+          
   $url = simple_paypal_get_url();
   $form['#action'] = $url;