can't run kafka example code

Hi, all

Here I want to run example code associated with kafka package, I run as
readme says:

To run the demo using scripts:

+ 1. Start Zookeeper and the Kafka server
+ 2. For simple consumer demo, run bin/java-simple-consumer-demo.sh
+ 3. For unlimited producer-consumer run, run
bin/java-producer-consumer-demo.sh

but I got such error,

:bin/../../project/boot/scala-2.8.0/lib/*.jar:bin/../../core/lib_managed/scala_2.8.0/compile/*.jar:bin/../../core/lib/*.jar:bin/../../core/target/scala_2.8.0/
*.jar:bin/../../examples/target/scala_2.8.0/*.jar

Error: Could not find or load main class kafka.examples.SimpleConsumerDemo

But I already build the package under kafka directory, I can see the
class in examples/target/classes/kafka/examples

Any idea about this issue?

thanks

Alec Li