strange error message: bad symbolic reference. A signature in package.class refers to term apache in package org which is not available

The message says "There's no package org.apache in my classpath, and I need it while reading file package.class". Pass -Ylog-classpath to scalac and look at what is the real classpath that gets to the compiler.

To me it was JDK not set on PATH neither JAVA_HOME

You can add JAVA_HOME to point to your JDK root folder and add jdk/bin folder (wich inludes javac) directly to the path.

You can refer to the Oracle docs for instruccions on how to add the path http://docs.oracle.com/javase/7/docs/webnotes/install/windows/jdk-installation-windows.html