diff --git a/hudson_build_release.sh b/hudson_build_release.sh
index 5f8edd4..e689e17 100755
--- a/hudson_build_release.sh
+++ b/hudson_build_release.sh
@@ -61,7 +61,13 @@ echo "Assembling base package"
 cd $WORKSPACE
 
 echo "Syncing base packages files from sphere.telascience.org"
-rsync -avz --filter 'merge base-package.rules' \
+
+# a: archive mode
+# z: compress
+# delete: 'delete extraneous files from dest dirs'; avoid bug 1344
+# filter: use the rules in our rules file
+rsync -az --delete \
+ --filter 'merge base-package.rules' \
  -e ssh jturner@sphere.telascience.org:/home/jturner/fgdata .
 
 tar cjf output/FlightGear-$VERSION-data.tar.bz2 fgdata/