I get some soure from net. and import on my workspace. When i run on emulator, its throws,

```
 "05-28 17:30:47.895: E/AndroidRuntime(840): java.lang.RuntimeException: Unable to instantiate activity 
ComponentInfo{com.developmentmill.laserlogic/com.developmentmill.laserlogic.StageActivity}:
 java.lang.ClassNotFoundException: com.developmentmill.laserlogic.StageActivity in
 loader dalvik.system.PathClassLoader[/data/app/com.developmentmill.laserlogic-2.apk]"

```

But when i run the same code on my friend machine, its running without any error.

My eclipse ADT Version is 17.0 my friend eclipse ADT version is 16.0

I copy the jar files from lib folder to libs foder. and change the java build path from lib to libs folder. and also i cleaned the project. 

Again, i run the project, the same error has been throw.

What is the problem and how to correct it? y its occur on my machine only. Pls help me.