prev/next post buttons that skip a category

Hello,

i recently got my site up and running…
grayhood.com
simplex theme

i managed to use some plug ins so that any post with the category “sketches” will appear on its own page.

now my issue is on the single post pages i would like the prev/next links to skip the sketches category and go directly to the next chronological post.

this is the code for my current prev/next post buttons…

previous: <?php previous_post('%', '', 'yes'); ?> 

| next: <?php next_post('%', '', 'yes'); ?></small></div>

i have tried using this…

<?php next_post_link('%link', 'Next post in category', FALSE, '3'); ?>

…but then if the next post is in the sketches category no next button will display at all.

how do i make sure the next buttons will always point to the next chronological post skipping over category 3???

many thanks to anyone with advice.