Hi!
How is your link being stored?
Are you storing it as www.website.com or www.website.com
You will need to include the http:// either in your database, or as part of the link....
<a href="http://<?php echo ($row_rs_job['url']); ?>" target="_Blank"><?php echo ($row_rs_job['url']); ?></a>
Otherwise your browser will not know what to do with the URL.
Cheers
Ian