紧急求助：mahout安装配置后，执行mahout --help命令总是报错cl?报错

0.7和0.8版本的mahout都试过了，每次执行mahout命令就报以下错误

hadoop@ps-HP-ProBook-4416s:/usr/local$ mahout -version
MAHOUT_LOCAL is not set; adding HADOOP_CONF_DIR to classpath.
Exception in thread "main" java.lang.NoClassDefFoundError: classpath
Caused by: java.lang.ClassNotFoundException: classpath
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
Could not find the main class: classpath.  Program will exit.
Running on hadoop, using /usr/local/hadoop/bin/hadoop and HADOOP_CONF_DIR=/usr/local/hadoop/conf
MAHOUT-JOB: /usr/local/mahout-7/mahout-examples-0.7-job.jar

有没有哪位遇到过这一问题，请求帮助呀！紧急求助！谢谢！