The API is returning the following error message when I request the revision history for locked posts.

Example URL: http://api.stackoverflow.com/1.1/revisions/194812

    {
      "error": {
        "code": 500,
        "message": "A generic error has occurred on the server; developers have been notified."
      }
    }

I've tried this through the [API Console][1], directly in my browser, and in code (with and without an API key).

Here's a sample from some of the top posts on Stack Overflow.

Locked:

- [List of freely available programming books][2]
- [What is the single most influential book every programmer should read?][3]
- [Hidden Features of C#?][4]
- [Strangest language feature \[closed\]][5]
- [What are the lesser known but cool data structures?][6]

Not locked:

- [Hidden features of Python][7]
- [Flash CS4 refuses to let go][8]
- [What IDE to use for Python?][9]
- [What is the name of this operator: “-->”?][10]
- [RegEx match open tags except XHTML self-contained tags][11]
- [The Definitive C++ Book Guide and List][12]
- [Most useful free .NET libraries? \[closed\]][13]

All of the **locked** questions give the error message above, while all of the questions that are not locked return a normal revision history.  Other question states like **closed** and **protected** seem to have no effect.

Finally, I did one last test.  I was able to successfully fetch the revision history of [Twitter image encoding challenge \[closed\]][14] before it was locked (note that is was protected and closed prior to testing) but after it was locked I got [the same error message][15].


  [1]: http://api.stackoverflow.com/1.1/usage/methods/revisions
  [2]: http://api.stackoverflow.com/1.1/revisions/194812
  [3]: http://api.stackoverflow.com/1.1/revisions/1711
  [4]: http://api.stackoverflow.com/1.1/revisions/9033
  [5]: http://api.stackoverflow.com/1.1/revisions/1995113
  [6]: http://api.stackoverflow.com/1.1/revisions/500607
  [7]: http://api.stackoverflow.com/1.1/revisions/101268
  [8]: http://api.stackoverflow.com/1.1/revisions/2193953
  [9]: http://api.stackoverflow.com/1.1/revisions/81584
  [10]: http://api.stackoverflow.com/1.1/revisions/1642028
  [11]: http://api.stackoverflow.com/1.1/revisions/1732348
  [12]: http://api.stackoverflow.com/1.1/revisions/388242
  [13]: http://api.stackoverflow.com/1.1/revisions/662956
  [14]: https://stackoverflow.com/questions/891643/twitter-image-encoding-challenge
  [15]: http://api.stackoverflow.com/1.1/revisions/891643