Merging to-do/task lists from multiple inbox folders

Hi-

I am using Outlook 2007 and am trying to figure out how to merge to-do/task
lists from multiple inbox folders. I have my inbox associated with my name,
and then also a folder with my name that is associated with another inbox
that is used by several people on one project. (When emails come into the
latter folder, I sort the ones that I can deal with into the subfolder with
my name.) For my personal inbox, I can flag emails and they will pop up in my
to-do box, but when I flag things in my sub-folder they don't show up in my
to-do box, and I can't figure out where they end up. How can I make it so
that anything I flag with go into my to-do box? Thanks!