求助 b3log maven build 报错

GAE 和 maven 用的不多，使用 eclipse3.7
从 git fetch 之后
参照 https://github.com/b3log/b3log-solo/wiki/Ide build，到
7.下载 GAE SDK。右键 solo-gae 项目，Run as → Maven build… → Goals: gae:unpack
时，报错如下

[ERROR] No plugin found for prefix 'gae' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (C:\Documents and Settings\xiao\.m2\repository), m2-release (http://m2-repos.googlecode.com/svn/release), m2-snapshot (http://m2-repos.googlecode.com/svn/snapshot), central (http://repo.maven.apache.org/maven2)] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.

应该是找不到 eclipse，下载 GAE 后直接解压，环境变量里面设置了 GAE_HOME，没其他设置
请问该如何设置？
多谢！