Retrofit detected an unsupported OkHttp on the classpath error in OKHttp 2.0-open source projects square/okhttp

I am using Retrofit-1.6.0 + okhttp-2.0.0-RC1 in my project . when i run the project i get the error.

java.lang.RuntimeException: Retrofit detected an unsupported OkHttp on the classpath.
To use OkHttp with this version of Retrofit, you'll need:
1. com.squareup.okhttp:okhttp:1.6.0 (or newer)
2. com.squareup.okhttp:okhttp-urlconnection:1.6.0 (or newer)
Note that OkHttp 2.0.0+ is supported!

Anybody knows how to fix this?