diff --git a/src/main/java/org/gcube/portlets/user/newsfeed/server/NewsServiceImpl.java b/src/main/java/org/gcube/portlets/user/newsfeed/server/NewsServiceImpl.java
index 594235b..9a87f10 100644
--- a/src/main/java/org/gcube/portlets/user/newsfeed/server/NewsServiceImpl.java
+++ b/src/main/java/org/gcube/portlets/user/newsfeed/server/NewsServiceImpl.java
@@ -1146,7 +1146,7 @@ public class NewsServiceImpl extends RemoteServiceServlet implements NewsService
 			Calendar oneYearAgo = Calendar.getInstance();
 			oneYearAgo.set(Calendar.YEAR, oneYearAgo.get(Calendar.YEAR) - 1);
 
-			ArrayList<Feed> feeds = null;
+			List<Feed> feeds = null;
 
 			switch(action){
 			case POSTS_MADE_BY_USER:
@@ -1197,8 +1197,8 @@ public class NewsServiceImpl extends RemoteServiceServlet implements NewsService
 			// sort the list, retrieve elements in the range and enhance the feeds
 			Collections.sort(feeds, Collections.reverseOrder());
 			int upperIndex = (from + quantity) >= feeds.size() ? feeds.size() - 1 : from + quantity;
-			feeds = (ArrayList<Feed>) feeds.subList(from, upperIndex);
-			return enhanceFeeds(feeds, -1);
+			feeds = new ArrayList<Feed>(feeds.subList(from, upperIndex));
+			return enhanceFeeds((ArrayList<Feed>) feeds, -1);
 
 		}catch(Exception e){
 			_log.error("Error while retrieving feeds for user " + userid + " and action " + action.toString(), e);