Maven编译Hadoop的trunk项目报错:exec (compile-proto)

[INFO] Apache Hadoop Annotations ……………………. SUCCESS [4.657s]
[INFO] Apache Hadoop Auth ………………………….. SUCCESS [1.359s]
[INFO] Apache Hadoop Auth Examples ………………….. SUCCESS [0.868s]
[INFO] Apache Hadoop Common ………………………… FAILURE [1.065s]
[INFO] Apache Hadoop Common Project …………………. SKIPPED
[INFO] ————————————————————————
[INFO] BUILD FAILURE
[INFO] ————————————————————————
[INFO] Total time: 8.685s
[INFO] Finished at: Sat Jan 19 05:09:38 CST 2013
[INFO] Final Memory: 12M/183M
[INFO] ————————————————————————
[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2:exec (compile-proto) on project hadoop-common: Command execution failed. Process exited with an error: 1(Exit value: 1) -> [Help 1]

解决方法：

1，http://protobuf.googlecode.com/files/protobuf-2.4.1.tar.gz 下载

解压，进目录
./configure –prefix=/usr/local
make
make check
sudo make install

export L