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

What version are you running?
Review Board RC3 r2004

What's the URL of the page containing the problem?
/r/123/

What steps will reproduce the problem?
1. Use Opera 9.64 to update diff
2.
3.

What is the expected output? What do you see instead?
Expected: Diff uploaded, dialog opens to ask for comments and publish.
Actual: Error occurs, but reload the page everything is fine.

Error: Saving the form failed due to a server error: 0 n/a

Please try again later. If this continues to happen, please report it to 
your administrator.

Details:
{"stat": "ok", "diffset_id": 154}

What operating system are you using? What browser?
Windows, Opera 9.64

Please provide any additional information below.
IE8 tested OK.