Hi, I'm a chinese boy! When I trace the hello-world example,I get a error. The error code is like this: C:\Documents and Settings\张波\hello-world>mvn site [INFO] Scanning for projects... [INFO] ------------------------------------------------------------------------- --- [INFO] Building hello-world [INFO] task-segment: [site] [INFO] ------------------------------------------------------------------------- --- [INFO] ------------------------------------------------------------------------ [ERROR] BUILD ERROR [INFO] ------------------------------------------------------------------------ [INFO] The plugin 'org.apache.maven.plugins:maven-site-plugin' does not exist or no valid version could be found [INFO] ------------------------------------------------------------------------ [INFO] For more information, run Maven with the -e switch [INFO] ------------------------------------------------------------------------ [INFO] Total time: < 1 second [INFO] Finished at: Mon Jan 28 10:23:06 CST 2008 [INFO] Final Memory: 1M/2M [INFO] ------------------------------------------------------------------------ Can you help me?Waiting for your help! Thanks a lot! bobin.