static FacesMessage getErrorMessage(FacesContext facesContext,
    String messageId,
    Object[] args) 
{
        return getMessage(facesContext,
                          facesContext.getViewRoot().getLocale(),
                          FacesMessage.SEVERITY_ERROR,
                          messageId,
                          args);
}

 static FacesMessage getMessage(FacesContext facesContext,
    Locale locale,
    Severity severity,
    String messageId,
    Object[] args) 
{
        ResourceBundle appBundle;
        ResourceBundle defBundle;
        String summary;
        String detail;
        appBundle = getApplicationBundle(facesContext, locale);
        summary = getBundleString(appBundle, messageId);
        if (summary != null)
        {
            detail = getBundleString(appBundle, messageId + DETAIL_SUFFIX);
        }
        else
        {
            defBundle = getDefaultBundle(facesContext, locale);
            summary = getBundleString(defBundle, messageId);
            if (summary != null)
            {
                detail = getBundleString(defBundle, messageId + DETAIL_SUFFIX);
            }
            else
            {
                //Try to find detail alone
                detail = getBundleString(appBundle, messageId + DETAIL_SUFFIX);
                if (detail != null)
                {
                    summary = null;
                }
                else
                {
                    detail = getBundleString(defBundle, messageId + DETAIL_SUFFIX);
                    if (detail != null)
                    {
                        summary = null;
                    }
                    else
                    {
                        //Neither detail nor summary found
                        return null;
                    }
                }
            }
        }
        if (args != null && args.length  > 0)
        {
            MessageFormat format;
            if (summary != null)
            {
                format = new MessageFormat(summary, locale);
                summary = format.format(args);
            }
            if (detail != null)
            {
                format = new MessageFormat(detail, locale);
                detail = format.format(args);
            }
        }
        return new FacesMessage(severity, summary, detail);
}