>I would like it to open in a different template.
Don't understand what it meant by different template. For those matter, you have to think in terms of html spec rather than xsl template language. When you set up the <a> add an attribute target along with href. For instance, it would open in a new window if it is "_blank".
[tt]<a href="..." target="_blank">...</a>[/tt]
If the "different template" output set up an iframe, put the target attribute pointing to that "different" iframe...