does not work with IOException?

[Song Qiu]

I use <error-page> to do global error handling. It works perfectly for
ServletException. I can see the eror page displayed properly. But for
IOException, It does not work, I can only see a blank page. 

Here is part of my web.xml: 
<error-page> 
<!-- This is to catch any ServletException --> 
<exception-type>javax.servlet.ServletException</exception-type> 
/GenericErrorForward.jsp 
</error-page> 

<error-page> 
<!-- This is to catch any IOException --> 
<exception-type>java.lang.IOException</exception-type> 
/GenericErrorForward.jsp 
</error-page> 

Thanks.

Song