long to string value conversion doesn't work properly

```
What steps will reproduce the problem?
1. Have a class with a param type long
2. Convert the class to json
3. Notice that the json value for the long param is incorrect

What is the expected output? What do you see instead?
expected: 2877292185075667242
I see: 2877292185075600042

What version of the product are you using? On what operating system?
2.2.4 - windows 7, Java 7

Please provide any additional information below.

```

Original issue reported on code.google.com by `delta2...@gmail.com` on 8 Mar 2014 at 6:06