web.xml question

I have a web application that has 2 filters and a welcome file
configured in the web.xml.  The filters work when the url running the
app explicitly contains a page, i.e.  http://xxx/webapp/page.jsp.  If
the url doesn't contain a page, i.e. http://xxx/webapp/  the filters are
ignored, but the welcome page is found correctly.  What am I doing
wrong?  Here is my web.xml
 
<filter> 
    <filter-name>Filter1</filter-name> 
    <filter-class>Filter1</filter-class> 
  </filter>
  <filter-mapping> 
    <filter-name>Filter1</filter-name>
    <url-pattern>/*</url-pattern>   
  </filter-mapping> 
 
  <filter> 
    <filter-name>Filter2</filter-name> 
    <filter-class>Filter2</filter-class> 
      </filter>
   <filter-mapping> 
    <filter-name>Filter2</filter-name>
    <url-pattern>/*</url-pattern> 
  </filter-mapping> 
 
 <welcome-file-list>
  <welcome-file>page.jsp</welcome-file>
 </welcome-file-list>