title: Why does recursive submodule update from github fail for DoctrineMongoORMModule?
body: <p>Is this something I am doing wrong, or a wider bug?</p>
  
  <p>If I execute the following git commands in an empty directory:</p>
  
  <pre><code>git init
  git submodule add https://github.com/doctrine/DoctrineMongoODMModule \vendor\DoctrineMongoODMModule
  git submodule update --init --recursive
  </code></pre>
  
  <p>The all goes well, multiple submodules are pulled, and then it fails with the following output:</p>
  
  <pre><code>fatal: not a git repository: ../../../../../../../../../../.git/modules/vendor/DoctrineMongoODMModule/modules/vendor/mongodb-odm/modules/lib/vendor/doctrine-mongodb/modules/lib/vendor/doctrine-common
  Unable to find current revision in submodule pat 'lib/vendor/doctrine-common'
  </code></pre>
  
  <p>I've done a bit more digging. The .git file in the submodule that is causing the problem has the following contents:</p>
  
  <pre><code>gitdir: ../../../../../../../../../../.git/modules/vendor/DoctrineMongoODMModule/modules/vendor/mongodb-odm/modules/lib/vendor/doctrine-mongodb/modules/lib/vendor/doctrine-common
  </code></pre>
  
  <p>I have checked that gitdir path, and it does exist. However, I am using a Windows XP machine and if I attempt this from the cmd prompt I have problems:</p>
  
  <pre><code>C:\xds\sds\vendor\DoctrineMongoODMModule\vendor\mongodb-odm\lib\vendor\doctrine-
  mongodb\lib\vendor\doctrine-common&gt;cd ../../../../../../../../../../.git/modules
  /vendor/DoctrineMongoODMModule/modules/vendor/mongodb-odm/modules/lib/vendor/doc
  trine-mongodb/modules/lib/vendor/doctrine-common
  The system cannot find the path specified.
  </code></pre>
  
  <p>It appears that the directory change string is too long, because if I split it into two parts it works:</p>
  
  <pre><code>C:\xds\sds\vendor\DoctrineMongoODMModule\vendor\mongodb-odm\lib\vendor\doctrine-
  mongodb\lib\vendor\doctrine-common&gt;cd ../../../../../../../../../../.git/modules
  /vendor/DoctrineMongoODMModule/modules/vendor/mongodb-odm/modules/lib/vendor/doc
  trine-mongodb/
  
  C:\xds\sds\.git\modules\vendor\DoctrineMongoODMModule\modules\vendor\mongodb-odm
  \modules\lib\vendor\doctrine-mongodb&gt;cd modules/lib/vendor/doctrine-common
  
  C:\xds\sds\.git\modules\vendor\DoctrineMongoODMModule\modules\vendor\mongodb-odm
  \modules\lib\vendor\doctrine-mongodb\modules\lib\vendor\doctrine-common&gt;
  </code></pre>
  
  <p>Any advice or help would be appreciated.
  Cheers.</p>