Tag library definition

Hi,

Are there any tag libraries available for producing code that conforms to
the standards set by the WAI or Section 508 in praticular?

Is there a .tld file that handles taking care of certain things that should
be added to html tags that are usually omitted by the everyday application
developer?

To be more specific, I am a java developer working on a Struts application
and am looking for a tag library to assist in the production of code that
meets accessibility standards.

Thanks!