[Zope] stuck with parameters

[prabuddha ray]

Thanks fo rthe support but by the time i read the soln. by AJ i 
tried to rebuild the
whole page in a dtml document . earlier i was trying page 
template.

Now in the DTML-IN tag used to fill the data in my 2nd combobox in 
my form i'm
using a ZSQL method with one param districtname. this value i've 
to get from the
submit of the same form upon selecting from 1st combobox ' 
districtname'.

the  dtml-in tag i used goes like this:
<dtml-in getDistrictUser 
(districtname=REQUEST.form.districtname)>
<dtml-var username>
</dtml-in>

error on saving changes:

document template parse error,

invalid attribute name getDistrictUser(districtname
for tag "<dtml-in...."


both the parameter name n the first combobox name is 
"districtname" . i made them
similar thinking it wud take the request variable automatically.

plz help me out sir.