diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/CommonServerLogger.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/CommonServerLogger.java
index 3dd15b719ba57b9ed7d79ce21161b72eb05b3d34..1c7726af1db88128fa724c63b493f5f68c742f4c 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/CommonServerLogger.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/CommonServerLogger.java
@@ -1636,7 +1636,7 @@ final class CommonServerLogger extends AbstractServerLogger implements ICommonSe
             DatastoreServiceDescription serviceDescription, Map<String, Object> parameters)
     {
         logAccess(sessionToken, "createReportFromAggregationService",
-                "SERVICE(%s), PARAMETERS(%s)", serviceDescription, parameters);
+                "SERVICE(%s), PARAMETERS(%s)", serviceDescription, parameters.keySet());
         return null;
     }