Index: modules/poll/poll.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/poll/poll.module,v
retrieving revision 1.262
diff -u -r1.262 poll.module
--- modules/poll/poll.module	9 Jan 2008 09:51:34 -0000	1.262
+++ modules/poll/poll.module	13 Jan 2008 01:32:56 -0000
@@ -586,6 +586,15 @@
 }
 
 /**
+ * Validation function for processing votes
+ */
+function poll_view_voting_validate($form, &$form_state) { 
+  if ($form_state['values']['choice'] == -1) {
+    form_set_error( 'choice', t('Your vote could not be recorded because you did not select any of the choices.'));
+  }
+}
+
+/**
  * Submit handler for processing a vote
  */
 function poll_vote($form, &$form_state) {