We are running a roundup based tracker on
issues.fresco.org.

When (trying to) edit a bug older then about 8 month I
get "Error: activity" whenever I try to change
something. The message gets appended and send out via
mail, even inspite of that error (with all changes
documented), all other changes get ignored.

When reloading the bug-page even the message is gone.
We are using roundup 0.6.0. Any ideas?