Tag lib not found under tomcat 6.0 but is found under VMWare vFabric server - why?

My Roo app is working great within STS when run on the VMWare vFabric server.

But when I run under tomcat 6.0, both within STS and on my ISP, I get tag lib not found error.

Google is telling me other people have had this error, but not recently.

A cut down version of the error is below and the pom attached. I am using the latest versions of STS and Roo.

Thanks for any help.

It would also help to know if anyone has NOT had this problem, as that might point to some setting in my STS or Tomcat environments.

Code:

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HTTP Status 500 -

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.tiles.impl.CannotRenderException: ServletException including path '/WEB-INF/layouts/default.jspx'.
        org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:692)
        org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:644)
        org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:627)
        org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:321)
        org.springframework.web.servlet.view.tiles2.TilesView.renderMergedOutputModel(TilesView.java:124)
        org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:262)
        org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1180)
        org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:950)
        org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
        org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
        org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
......
        org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
root cause

org.apache.tiles.util.TilesIOException: ServletException including path '/WEB-INF/layouts/default.jspx'.
        org.apache.tiles.servlet.context.ServletUtil.wrapServletException(ServletUtil.java:243)
        org.apache.tiles.servlet.context.ServletTilesRequestContext.forward(ServletTilesRequestContext.java:243)
        org.apache.tiles.servlet.context.ServletTilesRequestContext.dispatch(ServletTilesRequestContext.java:222)
        org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
        org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
        org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)

.......

        org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
        org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
root cause

org.apache.jasper.JasperException: /WEB-INF/layouts/default.jspx(1,239) Could not add one or more tag libraries.
        org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)
        org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
        org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:88)
        org.apache.jasper.compiler.JspDocumentParser.parse(JspDocumentParser.java:216)

....

note The full stack trace of the root cause is available in the Apache Tomcat/6.0.24 logs.

Apache Tomcat/6.0.24

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