checkout指定tag

cd /path/to/yoursubmodule

git checkout yourTag

cd ..

git add yoursubmodule

git commit -m "use submoduile at tag xx"

git push

http://*.com/questions/18755933/create-a-git-submodule-from-a-specific-repo-hash-or-tag删除submodule

从 .gitmodule 文件里面删掉关于 vendor/plugins/will_paginate 的配置信息
git rm –cached vendor/plugins/will_paginate 
现在可以重新添加了

http://huacnlee.com/blog/how-to-remove-submodule-in-git/