groovy/modules/grails/src/war/WEB-INF/sitemesh.xml

<sitemesh>
    <page-parsers>
        <parser content-type="text/html"
            class="com.opensymphony.module.sitemesh.parser.FastPageParser" />
        <parser content-type="text/html;charset=ISO-8859-1"
            class="com.opensymphony.module.sitemesh.parser.FastPageParser" />
        <parser content-type="text/html;charset=UTF-8"
            class="com.opensymphony.module.sitemesh.parser.FastPageParser" />            
    </page-parsers>

    <decorator-mappers>
        <mapper class="org.codehaus.groovy.grails.web.sitemesh.GrailsLayoutDecoratorMapper" />
    </decorator-mappers>
</sitemesh>