saving the user id for thumbnails using attachment_fu

I am using attachment_fu to create thumbnails, and it is working
great. However, I am have a view with all my users thumbnails
displayed and am trying to make it so when you click on a thumbnail of
their avatar, it shows that users profile. In order to accomplish
this I have saved a user_id identifier for each avatar, but the
problem is that attachment_fu only saves this user_id for the main
image and does not save it in the column for the thumbnail. So when I
try and access the user_id to display the corresponding profile, it
says the user_id is 0 and there is no user with that id. Is there any
way to get attachment_fu to save the user_id to the thumbails too?
Perhaps there is some other solution. Heres the code for the avatars
so you can get a sense for what I am trying to do:

<% for avatar in @avatar -%>

<%= link_to image_tag(avatar.public_filename()), {:action =>
"index", :controller => "users", :user_id => avatar.user_id } %>

<% end %>
So this user_id is 0 b/c the attachment_fu didnt save the user_id

Any ideas are greatly appreciated. Thanks, Dave