如何在Eclipse for Android开发中使用它来检查/升级Proguard版本？

The documentation on this is extremely poor. I understand that ProGuard can be enabled by manually editing "default.properties" in the project's rot directory. And all the settings go into the "proguard.cfg" file in the same place, but I'd like to know which version of ProGuard is being used (I'm using Eclise Indigo). I would also like to be able to upgrade it to the latest versions whenever the are released. But I can't find any reference on how to do it.The documentation on this is extremely poor. I