It's great that you are keen to have something that's accessible with JS off, but it may be more trouble than it's worth to try to reform that script. Here's a gallery that degrades nicely without pulling the ball and chain of jQuery along behind it:
Many thanks for your reply. Yes I think it is important to consider non js browsers (currently have over 1200 views a month without js enabled). I think I have managed to do it using document.writes for the tabs on the right then repeat the code in the noscript tag (changing the url to the actual page). So if JS disabled, you still get the tabs but the links go to the page. This seems to work nicely and gets round the problem.
The link you sent would not work as I am not using it as an image viewer, I have had to remove the images and replace with html content and it is also fluid depending on browser width.
That's OK, it's just interesting to know the field it applies to. A lot of people are skeptical about the need to design for the JS off scenario, so your comments above are a salutary example of why it's necessary. Thanks for your feedback. I'm going to bookmark this thread for future reference!