Forum OpenACS Q&A: bug tracker
Thank you for your help
That will bring you to a page listing all of the packages that bugtracker depends on that the package manager must load (it's a confirmation page, essentially).
You can also find the first-order dependencies in the bugtracker.info XML file in the package itself. However this won't tell you what packages those packages in turn depend upon.
One package I know it depends on is the workflow package...
Between the two, though, you should be able to figure out everything it depends on.