Validation with cck tab forms

Here's a code example; clicking on this tab-switch would validate just one element in the form instead of the whole form. element() would return false if the element failed to validate, in which case you could have logic to not switch tabs:

$("#my-tab-switch").click(function() {
  $("#my-form").validate(my-validate-object).element("#my-element");
} );

By the way, the docs at http://docs.jquery.com/Plugins/Validation are for the latest version of the plugin, which requires jQuery 1.2 and is available only in the Drupal 6 branch of this module.

Please re-open if you have more questions.