我从以下位置下载了flume源代码：https://github.com/cloudera/flume/tarball/release-0.9.4
我得到一个nullpointerexception，如下所示。如果有人有任何建议，将不胜感激。
我运行mvn compile:

[INFO] Scanning for projects...
[INFO] Reactor build order: 
[INFO]   Flume
[INFO]   Flume Core
[INFO]   Flume Master Config Web Application
[INFO]   Flume Node Web
[INFO]   Flume Distribution Project
[INFO]   A log4j appender for Flume
[INFO]   Flume Hello World Plugin
[INFO]   Flume HBase Plugin
[INFO] ------------------------------------------------------------------------
[INFO] Building Flume
[INFO]    task-segment: [compile]
[INFO] ------------------------------------------------------------------------
[INFO] No goals needed for project - skipping
[INFO] ------------------------------------------------------------------------
[INFO] Building Flume Core
[INFO]    task-segment: [compile]
[INFO] ------------------------------------------------------------------------
Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.3/maven-resources-plugin-2.3.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.3/maven-resources-plugin-2.3.jar

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-provider-api/1.0-beta-2/wagon-provider-api-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon/1.0-beta-2/wagon-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-file/1.0-beta-2/wagon-file-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-providers/1.0-beta-2/wagon-providers-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-http-lightweight/1.0-beta-2/wagon-http-lightweight-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-http-shared/1.0-beta-2/wagon-http-shared-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/jtidy/jtidy/4aug2000r7-dev/jtidy-4aug2000r7-dev.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-ssh-external/1.0-beta-2/wagon-ssh-external-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-ssh-common/1.0-beta-2/wagon-ssh-common-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/org/apache/maven/wagon/wagon-ssh/1.0-beta-2/wagon-ssh-1.0-beta-2.pom

Downloading: http://repo1.maven.org/maven2/com/jcraft/jsch/0.1.27/jsch-0.1.27.pom

[INFO] [cloudera-buildnumber:create {execution: default}]
[INFO] Checking for local modifications: skipped.
[INFO] Updating project files from SCM: skipped.
[INFO] ------------------------------------------------------------------------
[ERROR] FATAL ERROR
[INFO] ------------------------------------------------------------------------
[INFO] null
[INFO] ------------------------------------------------------------------------
[INFO] Trace
java.lang.NullPointerException
    at org.codehaus.mojo.build.CreateMojo.getRevision(CreateMojo.java:736)
    at org.codehaus.mojo.build.CreateMojo.execute(CreateMojo.java:460)
    at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLifecycle(DefaultLifecycleExecutor.java:556)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:535)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
    at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
    at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
    at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 8 seconds
[INFO] Finished at: Fri Sep 09 14:56:37 PDT 2011
[INFO] Final Memory: 12M/81M
[INFO] ------------------------------------------------------------------------