I believe that the problem with pollpal.php is probably more of a problem with doexpirethreads.php.
If you create a thread that contans a poll in it, then delete that poll (not the whole thread, just the post containing the poll) the Poll Number is still contained in w3t_Posts.B_Poll.
This means that pollpal.php (and polllistpal.php) will still see it as a valid poll, and try to display it.
I thought of adding an update query to doexpirethreads.php to delete the data in B_Poll when you delete the post, but I am not sure how that would affect threads with multiple polls in it.
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