[Zope] Strange redirect problem -- can someone assist?

[Dennis Allison]

We frequently use a design pattern which uses a multi-part form on a page.  
The form is populated from a RDBMS.  Multiple submit buttons capture the
function to be performed.  The form action routine breaks into a case-like
if-elif-else statement.  Each action (e.g,, 'add', 'edit', 'delete') is
implemented as a separate block of code. The form uses <POST> to transfer
parameters (all strings or empty) to the action.  The action grabs the
parameters, performs its function, and then continues in the application
flow as needed, transferring control using a redirect to the desired URL
with appended CGI parameter. Frequently the redirect simply return to the 
original form for further modification. 

My problem:  In one form for one submit button, the redirect appears to
fail.  The action is performed but the page to which the action redirects
upon completion is never displayed.  Other actions from the same form work
fine.  We have been trying to isolate the problem, but have not been
successful--everything looks correct, but we still see the one failure.  
Nearly identical code in other parts of the system works fine.

Any suggestions would be appreciated.  Is there somthing subtle and 
unusual about the way Zope 2.11 manages redirects?  

Zope 2.11
Python 2.4.X
x86_64 processor running Centos 5.1

Thanks.  -d
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