[Zope] Acquistion mistery

[D2]

Hello,

i have three objects :
	testform (a ZPT)
	testscript (a PythonScript)
	testdtml (a DTML Method)
located in a standard Zope root.

I fill in testform fields then submit the form to testscript wich set a 
property (request.set('tesfield', 'Hi there') in the request and then 
calls testdtml with the request object.
testdtml displays REQUEST with the fields from testform and testfield 
set in tescript, without problems if i don't use <dtml-var 
standard_html_header>. If i do, the publisher returns a KeyError : 
standard_html_header.

I don't understand why standard_html_header is not acquired.

Does somebody explain to me how acquisition behaviour is affected by my 
stuff.

More generally, my goal is to understand how i can  pass parameters to 
forms from scripts, other forms and object methods so don't hesitate to 
feed me with some theory.

here is the source of testscript:

# Example code:
# Import a standard function, and get the HTML request and response objects.
from Products.PythonScripts.standard import html_quote
request = container.REQUEST
RESPONSE =  request.RESPONSE
request.set('testfield','Hi there')
destination=getattr(container,'testdtml')
kw={}
kw['REQUEST']=container.REQUEST
return apply(destination, (), kw)