Adding multiple upstream tasks is mildly broken

This morning, I attempted to add a third Debian task to bug #552954 with the "Also affects Distribution ..." thingy.

After I pick Debian in the dropdown on https://bugs.launchpad.net/ubuntu/+source/emacs-jabber/+bug/552954/+distrotask and click Continue, I get a warning box saying "Debian doesn't use Launchpad as its bug tracker. Without a bug URL to watch, the Debian status will not update automatically. [Add anyway]" Clicking on the "Add anyway" button adds a new bug task.

The new bug task has status "New"; when I click it open to expand it via the arrow on the left, I see two instances of the "None, the status of the bug is updated manually." radio button (apparently because there are already two remote bug watches?). Selecting the first one changes not only the task I'm editing, but also the previous upstream task I added.

Pardon if this is a bit hazy in the details; I report what I remember from the work I did on bug #552954