b2RopeJoint how to implement this into box2d?

How do I put b2RopeJoint into my project. The newest Box2d version does not have b2RopeJoint in it. People online tell me to update my box2d but I have 2.1.2 which is the newest version. I'm so confused. Will someone please tell me how to implement b2RopeJoint into my project? Please explain it to me 开发者_JAVA技巧in simple steps. I get confused easily unfortunately. Thanks!

---

2.1.2 is the newest official release, but the b2RopeJoint is newer than that. You will need to get the latest source from svn. http://code.google.com/p/box2d/source/checkout

---

Here is the new code ported for Box2D 2.1a:

http://blog.allanbishop.com/box2d-2-1a-rope-joint-ported-to-as3/

"Installation instructions: Save these files into the Box2D\Dynamics\Joints folder. b2Joint will overwrite the existing b2Joint."