[mod_python] util.FieldStorage(req).list

Hi,
my problem is with util.FieldStorage, I can't get information contained 
in content variable.
I call my form.py program from here:

...<form action= "/mailing/form.py/handler" method="post">...
catsel, subcatsel and idisel are checkbox.


MY form.py PROGRAM
---------------------------------------------
from mod_python import apache
from pg import DB
import string
from mod_python import util

def handler(req,catsel,subcatsel,idisel):
  req.content_type = "text/html"
  req.send_http_header()
  content = util.FieldStorage(req).list
---------------------------------------------

Can ne1 help me ?

Thanks.