There is not an enourmous amount of deployment control where I work at the moment. And while there is a long term plan to create a build script that deals with deployment at the
I also use Ant and have developed a special Task that is able to retrieve the Subversion information from a local repository (if the code was checked-out) or a remote Subversion server (if the code was exported) and makes them available via regular Ant properties.
Using Ant replacement mechanism (in the Copy task, for example), you can place these values wherever you see fit.