Patch for /trunk/doc/multithreading.txt

```
I've tried explain some more theory and made it up to date(changed to old code 
to the current code).
```

Original issue reported on code.google.com by `Leg3ndda...@gmail.com` on 18 Aug 2011 at 4:34

Attachments:
- [multithreading.txt.patch](https://storage.googleapis.com/google-code-attachments/jamesm-tutorials/issue-8/comment-0/multithreading.txt.patch)
