Changed the way that the sf.spec.sourcesync.enable property is used to control the syncing, so that it can sync test repos even if it's not syncing any source repos.
<?xml version="1.0"?>
<project name="SF-PACKAGE-REFS">
<path id="sf.spec.system.definition.files">
<fileset dir="${sf.spec.job.drive}/" casesensitive="false">
<include name="${sf.spec.systemdefinition.location}"/>
</fileset>
</path>
</project>