Index: webform.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/webform/webform.module,v
retrieving revision 1.124.2.45
diff -u -r1.124.2.45 webform.module
--- webform.module	23 Jul 2008 00:50:05 -0000	1.124.2.45
+++ webform.module	23 Jul 2008 01:28:43 -0000
@@ -1427,11 +1427,14 @@
         // Check if we're in a multipage form and determine the page number.
         if (!empty($form_state['storage']['submitted'])) {
           $page_num = $form_state['values']['details']['page_num'];
-          if ($form_state['values']['op'] == $prev_page && $page_num > 1) {
-            $page_num--;
-          }
-          else if ($form_state['values']['op'] == $next_page && $page_num < $page_count) {
-            $page_num++;
+          $errors = form_get_errors();
+          if (empty($errors)) {
+            if ($form_state['values']['op'] == $prev_page && $page_num > 1) {
+              $page_num--;
+            }
+            elseif ($form_state['values']['op'] == $next_page && $page_num < $page_count) {
+              $page_num++;
+            }
           }
         }
         else {