Explicitly uninstall bundles on failure rather than remove from region. If a subsystem fails to install, content and dependency bundles should be explicitly uninstalled rather than simply removing them from the region. Removal from a region does not result in the bundle being uninstalled; however, uninstalling a bundle does result in its removal from the region.
aries/trunk/subsystem/subsystem-core/src/main/java/org/apache/aries/subsystem/core/internal/BundleResourceInstaller.java