What version are you running?
SVN trunk

What's the URL of the page containing the problem?
http://rb.example.com/r/3/diff/

What steps will reproduce the problem?
1. Go to review page with screenshot: http://rb.example.com/r/3/diff/s/1/delete/
2. Click on [x] button near screenshot

What is the expected output?
Url http://rb.example.com/r/3/s/1/delete/ and screenshot is deleted.

What do you see instead?
Url http://rb.example.com/r/3/diff/s/1/delete/ and 404 error.