Missing a lot of Symbols in buildserver.serverside

Hello,

I´m realy new to Teamcity and I just started working on Unity_Runner. But in the moment I cannot build the initial state of the Plugin because I´m missing a lot of symbols and I´ve no Idea where to find the right libs.
Any help is appriciated.
This is was missing:

import jetbrains.buildServer.serverSide.BuildServerAdapter;
import jetbrains.buildServer.serverSide.BuildServerListener;
import jetbrains.buildServer.serverSide.SBuildServer;

import jetbrains.buildServer.serverSide.InvalidProperty;
import jetbrains.buildServer.serverSide.PropertiesProcessor;
import jetbrains.buildServer.serverSide.RunType;
import jetbrains.buildServer.serverSide.RunTypeRegistry;

with a compiler error like this:
java: cannot find symbol
  symbol:   class BuildServerAdapter
  location: package jetbrains.buildServer.serverSide

I´ve included:
TeamCity Install path /lib
TeamCity Install path /buildAgend/lib
TeamCity Install path /buildAgend/launcher/lib

Any idea what I´m missing here ?
Windows 8, IntelliJ Community 12.1.6, Teamcity 8.0.4

Thanks in advance

Friedrich Wessel