JSTL Fuctions Tab Library

Has anyone been able to use the functions in the JSTL tag library?  If I try
to do a simple ${fn:length(bean.property)}, my output is the same
${fn:length(bean.property)}.  I have also tried to use <c:if
test="${fn:contains(string, string)}"> and I get the following error message
in Tomcat:

 

ERROR org.apache.struts.taglib.tiles.InsertTag - ServletException in
'/tiles/MainLayout.jsp': ServletException in
'/tiles/ReportOptions-body.jsp': <h3>Validation error messages from
TagLibraryValidator for c</h3><p>403: tag = 'if' / attribute = 'test': An
error occurred while parsing custom action attribute "test" with value
"${fn:contains('audit', 'audit')}":
org.apache.taglibs.standard.lang.jstl.parser.ParseException: EL functions
are not supported.</p>

 

Thanks,

Chad