diff --git a/installation/resource/installer/bis-service.properties b/installation/resource/installer/bis-service.properties
index a6b05a8735ef40a6454dc135e2a1120d8e1a7682..1a89e00ffe0c87653fc535ef52cba669a167ab3e 100644
--- a/installation/resource/installer/bis-service.properties
+++ b/installation/resource/installer/bis-service.properties
@@ -2,4 +2,5 @@
 # This contents of this property file will be merged
 # in the installer distribution at build time.
 #
-database.kind=productive
\ No newline at end of file
+database.kind=productive
+jython-version=2.7
diff --git a/installation/resource/installer/dss-service.properties b/installation/resource/installer/dss-service.properties
index 3200f47fe5140f853a908b7cf45b8f321eca18b8..454da681358e698e4ef07217b858ea98b57e1da8 100644
--- a/installation/resource/installer/dss-service.properties
+++ b/installation/resource/installer/dss-service.properties
@@ -24,3 +24,5 @@ simple-dropbox.incoming-data-completeness-condition = auto-detection
 simple-dropbox.top-level-data-set-handler = ch.systemsx.cisd.etlserver.registrator.JythonTopLevelDataSetHandler
 simple-dropbox.script-path = ${root-dir}/dropboxes/simple-dropbox.py
 simple-dropbox.storage-processor = ch.systemsx.cisd.etlserver.DefaultStorageProcessor
+
+jython-version=2.7