[Zope] standard_error_message question

[AM]

Hi,
I was trying out the suggestions regarding custom error handling mentioned @
http://www.zope.org/Members/JohnC/StandardErrorMessage

and put a simple

<dtml-if "error_type=='NotFound'">
  <dtml-call "RESPONSE.redirect(errors.e404.absolute_url())">
</dtml-if> 

at the top of my standard_error_message.

Unfortunately when I try to hit a non-existant page I do not get 
redirected to the right page, I still get the Debugging Notice.... blah 
blah blah

If I put a <dtml-var error_type> at the top I do get the NotFound at the 
top of the error page.

WHy is this not being handled.
TIA
AM

-- 
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 Aseem Mohanty							   
 Neurobehavioral Systems Inc, 828 San Pablo Ave, Albany, CA 94706 
 (R) 510 7696011 (M) 510 3014871 (O) 510 5279231		  	
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 "I saw `cout' being shifted "Hello world" times to the left and  
  stopped right there!!"                        -- Steve Gonedes  
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