I always advise to show all tabs for users without javascript support.

  <div style="display: none">
    Hidden tab content
  </div>

Else noscript users would have to disable CSS to watch the above hidden tabs, pretty inexcusable. The "correct" progressive enhancement way to do this, is to show all the tabs, and use javascript to hide tabs from view from those that support javascript.

Basically it has always been a bad idea to "hardcode" visibility for tabs/divs.

For example visit: http://adwords.google.com/support/aw/bin/static.py?hl=nl&... without javascript support. The content is hidden for everyone and pressing expand won't do anything.

Compare with: http://www.google.com/support/webmasters/bin/answer.py?hl=en... . Even without javascript support you can still see the examples, because those are only hidden if you have javascript support.