compiling error

hi keel-users

i've got a compiling error (below) - as soon as i try to integrate the 
helloworld-application from the hands-on-tutorial. if i assemble-deploy 
without it, everything runs fine...
can anybody help me?

and another question: all my imports in eclipse can't be resolved as 
long as i don't add the corresponding jars. but what librarys should i 
add and from what directory? i can find the same jars in many 
directories...?

thanks and greetings
stefan

----------------------------

build:
      [echo] Compiling keel-server ...
     [javac] Compiling 75 source files to 
D:\java\Keel\keel-server\build\classes
     [javac] 
D:\java\Keel\keel-server\src\java\org\keel\clients\AbstractClientCon
nector.java:20: cannot access org.keel.services.model.KeelRequest
     [javac] bad class file: 
D:\java\Keel\keel-core\build\lib\keel-core-2.0.jar(o
rg/keel/services/model/KeelRequest.class)
     [javac] class file contains wrong class: 
keel-core.src.java.org.keel.service
s.model.KeelRequest
     [javac] Please remove or make sure it appears in the correct 
subdirectory of
  the classpath.
     [javac] import org.keel.services.model.KeelRequest;
     [javac]                                ^
     [javac] 1 error

BUILD FAILED
file:D:/java/Keel/keel-build/build-common.xml:145: Compile failed; see 
the compi
ler error output for details.