Broken links to submodules when staging site

The attached testcase has a broken link when staged, and the relative path to it looks horrible.

I had assumed that recent development in maven-doxia-tools might have been to address this issue, so I tried to reproduce with the latest SVN version. There I hit MSITE-315, so I'm reporting this for 2.0-beta-6 as well.

You might want to make a staging testcase out of this, and have links checked. I don't yet understand all the magic behind the integration tests, so I didn't provide a patch for this.