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The show and update function names are converted to lower case; all the methods of Tapestry.ElementEffect should have all lower-case names. Because client-side JavaScript is so fluid (new methods may be added to existing objects), Tapestry makes no attempt to validate the function names ... however, if the names are not valid, then the default show and highlight methods will be used.
Zones may only be used inside the body of a page, not the head.
More Information
For examples of extending a Form with a Zone and updating multiple zones at once, see the Ajax Components FAQ.
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