Sent information is lost when data is submitted after session has expired

1) Start filing a bug against Bamboo.
2) Wait 30 minutes (or however long the session timeout is).
3) Finish editing the bug.
4) Submit

Since your session is expired, you're taken to a page indicating that you don't have permission to submit a bug without logging in. All the work you have done is discarded. Hitting the back button does not take you back to the form you just submitted.