Custom tags must follow the rules of XML. When you have a beginning tag, you must have an ending tag that is the same as the beginning tab except that it starts with "/". The ending tag for your <html:link> must not be </a> but rather </html:link>. [ July 31, 2007: Message edited by: Merrill Higginson ]
The logic:redirect tag will do this. Be careful, though, as it must be executed before any portion of the JSP is rendered. Othewise, you'll get an error. For more details on this tag, see the heading "redirect" in this link.