*NOTE: Do not post confidential information in this bug report.*

What version are you running?
1.0.1

What's the URL of the page containing the problem?
javascript behaviour, when looking at diff between diff revisions
(http://reviewboardserver/r/x/diff/y-z/#

What steps will reproduce the problem?
1. Create an initial review (r1)
2. Update the review with additional files (r2)
3. Do a diff between r1-r2
4. Click on Expand for a diff tab for a file which was newly added on r2

What is the expected output? What do you see instead?
Expect to see the full file I attempted to expand, get a 404 tab at the top
of the page instead.

What operating system are you using? What browser?
reviewboard hosted on gnu/linux (python 2.5), issue spotted with firefox
3.5 under xp.

Please provide any additional information below.
using perforce as repository