[Zope] Subclassing problem?

[Chew Meng Kuan]

I have this class called Sample that is coded in python only. This class
needs to contain uploaded files. Currently, it subclasses the following:

CatalogAware, OFS.SimpleItem.Item, Persistent, Implicit,
AccessControl.Role.RoleManager, OFS.ObjectManager

As a test, I tried the following command where sample1 is an instance of
Sample:
$ python Client.py -usuperuser:123
http://localhost:8080/Test/sample1/manage_addFile id="forms.html"
file:file=/home/superuser/forms.html 

The file was added to sample1's parent folder
(http://localhost:8080/Test/forms.html) instead of itself
(http://localhost:8080/Test/sample1/forms.html). Why is this so? Is
there any particular Class I need to subclass in order for Sample to
contain File objects?

Thanks,
Meng Kuan