web.xml의 스키마가 조그 바뀌었네요. 그래서 <taglib> 엘레먼트를 직접 쓰지 못하고 <jsp-config> 하위에 써야 하나봐요. 아래처럼 사용하면 eclipse에서 에러표시가 나타나지 않아요.

<jsp-config>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-bean.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-bean.tld</taglib-location>
</taglib>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-html.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-html.tld</taglib-location>
</taglib>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-logic.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-logic.tld</taglib-location>
</taglib>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-nested.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-nested.tld</taglib-location>
</taglib>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-template.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-template.tld</taglib-location>
</taglib>
<taglib>
 <taglib-uri>/WEB-INF/tlds/struts-tiles.tld</taglib-uri>
 <taglib-location>/WEB-INF/tlds/struts-tiles.tld</taglib-location>
</taglib> 
</jsp-config>