diff --git a/distro/changelog.xml b/distro/changelog.xml
index 1bfcc55..82fb39a 100644
--- a/distro/changelog.xml
+++ b/distro/changelog.xml
@@ -3,6 +3,7 @@
 		date="2016-12-02">
 		<Change>removed asl session</Change>
 		<Change>Increased general performance and bugfixes</Change>
+		<Change>fetching of users list to mention in comments loaded on demand</Change>
 	</Changeset>
 	<Changeset component="org.gcube.portlets-user.news-feed.2-1-0"
 		date="2016-10-29">
diff --git a/src/main/java/org/gcube/portlets/user/newsfeed/client/ui/SuperPosedTextArea.java b/src/main/java/org/gcube/portlets/user/newsfeed/client/ui/SuperPosedTextArea.java
index 111bbaa..778337c 100644
--- a/src/main/java/org/gcube/portlets/user/newsfeed/client/ui/SuperPosedTextArea.java
+++ b/src/main/java/org/gcube/portlets/user/newsfeed/client/ui/SuperPosedTextArea.java
@@ -9,7 +9,6 @@ import java.util.HashSet;
 import org.gcube.portlets.user.gcubewidgets.client.elements.Div;
 import org.gcube.portlets.user.newsfeed.client.NewsService;
 import org.gcube.portlets.user.newsfeed.client.NewsServiceAsync;
-import org.gcube.portlets.user.newsfeed.client.panels.NewsFeedPanel;
 import org.gcube.portlets.widgets.pickitem.client.dialog.PickItemsDialog;
 import org.gcube.portlets.widgets.pickitem.client.events.PickedItemEvent;
 import org.gcube.portlets.widgets.pickitem.client.events.PickedItemEventHandler;
@@ -17,6 +16,8 @@ import org.gcube.portlets.widgets.pickitem.shared.ItemBean;
 
 import com.google.gwt.core.client.GWT;
 import com.google.gwt.dom.client.Element;
+import com.google.gwt.event.dom.client.FocusEvent;
+import com.google.gwt.event.dom.client.FocusHandler;
 import com.google.gwt.event.dom.client.KeyCodes;
 import com.google.gwt.event.dom.client.KeyPressEvent;
 import com.google.gwt.event.dom.client.KeyPressHandler;
@@ -38,7 +39,7 @@ public class SuperPosedTextArea extends TextArea {
 
 	private final HandlerManager eventBus = new HandlerManager(null);
 	
-	private PickItemsDialog pickUserDlg;
+	private PickItemsDialog pickUserDlg = null;
 	private Div highlighterDIV;
 	public final static int ARROW_UP = 38; 
 	public final static int ARROW_DOWN = 40; 
@@ -59,18 +60,6 @@ public class SuperPosedTextArea extends TextArea {
 		this.highlighterDIV = highlighterDIV;
 		//needed to give unique identifiers to the Area (for the jQuery plugin)
 		areaId = "postTextArea"+Random.nextInt();
-		
-		newsService.getOrganizationUsers(new AsyncCallback<ArrayList<ItemBean>>() {
-
-			@Override
-			public void onSuccess(ArrayList<ItemBean> users) {
-				pickUserDlg = new PickItemsDialog('@', users, eventBus, 460);				
-			}
-
-			@Override
-			public void onFailure(Throwable caught) {				
-			}
-		});
 		getElement().setAttribute("id", areaId); 
 		bind();
 		Timer t = new Timer() {
@@ -84,7 +73,23 @@ public class SuperPosedTextArea extends TextArea {
 		this.addKeyPressHandler(new KeyPressHandler() {			
 			@Override
 			public void onKeyPress(KeyPressEvent event) {
-				pickUserDlg.onKeyPress(getCursorPos(), event.getUnicodeCharCode(), getAbsoluteLeft(), getAbsoluteTop()+getOffsetHeight(), getText());	
+				if (pickUserDlg != null)
+					pickUserDlg.onKeyPress(getCursorPos(), event.getUnicodeCharCode(), getAbsoluteLeft(), getAbsoluteTop()+getOffsetHeight(), getText());	
+			}
+		});
+		this.addFocusHandler(new FocusHandler() {			
+			@Override
+			public void onFocus(FocusEvent event) {
+				newsService.getOrganizationUsers(new AsyncCallback<ArrayList<ItemBean>>() {
+					@Override
+					public void onSuccess(ArrayList<ItemBean> users) {
+						pickUserDlg = new PickItemsDialog('@', users, eventBus, 460);				
+					}
+
+					@Override
+					public void onFailure(Throwable caught) {				
+					}
+				});				
 			}
 		});
 		
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 7cea707..d58b44f 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
@@ -59,10 +59,12 @@ import org.gcube.vomanagement.usermanagement.exception.GroupRetrievalFault;
 import org.gcube.vomanagement.usermanagement.exception.TeamRetrievalFault;
 import org.gcube.vomanagement.usermanagement.exception.UserManagementSystemException;
 import org.gcube.vomanagement.usermanagement.exception.UserRetrievalFault;
+import org.gcube.vomanagement.usermanagement.exception.VirtualGroupNotExistingException;
 import org.gcube.vomanagement.usermanagement.impl.LiferayGroupManager;
 import org.gcube.vomanagement.usermanagement.impl.LiferayRoleManager;
 import org.gcube.vomanagement.usermanagement.impl.LiferayUserManager;
 import org.gcube.vomanagement.usermanagement.model.GCubeGroup;
+import org.gcube.vomanagement.usermanagement.model.GCubeTeam;
 import org.gcube.vomanagement.usermanagement.model.GCubeUser;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -85,7 +87,8 @@ public class NewsServiceImpl extends RemoteServiceServlet implements NewsService
 	private static final String REFRESH_TIME = "REFRESH_TIME";
 
 	private static final String SESSION_ADMIN_ATTR = "SESSION_ADMIN_ATTR";
-
+	public static final String NF_ORGANIZATIONUSERS_CACHE = "NF_ORGANIZATIONUSERS_CACHE";
+	public static final String LAST_RETRIEVED_TIME = "NF_LAST_RETRIEVED_TIME";
 
 	private String APP_ID;
 
@@ -893,12 +896,41 @@ public class NewsServiceImpl extends RemoteServiceServlet implements NewsService
 	}
 	@Override
 	public ArrayList<ItemBean> getOrganizationUsers() {
+		ArrayList<ItemBean> portalBeans = new ArrayList<ItemBean>();
 		PortalContext pContext = PortalContext.getConfiguration();
-		String userName = pContext.getCurrentUser(getThreadLocalRequest()).getUsername();
-		String currentScope = pContext.getCurrentScope(getThreadLocalRequest());
-		ArrayList<ItemBean> toReturn = Utils.getDisplayableItemBeans(currentScope, userName, isWithinPortal());
-		_log.trace("Returning " + toReturn.size() + " users for scope " + currentScope);
-		return toReturn;
+		GCubeUser currentUser = pContext.getCurrentUser(getThreadLocalRequest());
+		String userName = currentUser.getUsername();
+		UserManager um = new LiferayUserManager();
+		GroupManager gm = new LiferayGroupManager();
+		long currentGroupId = pContext.getCurrentGroupId(getThreadLocalRequest());
+		Set<GCubeUser> users = new HashSet<>();
+		List<GCubeTeam> teams = new ArrayList<>(); //TODO: teams should be added also in root Mode
+		try {
+			if (gm.isRootVO(currentGroupId)) {
+				Set<GCubeGroup> userGroups = gm.listGroupsByUserAndSite(currentUser.getUserId(), getThreadLocalRequest().getServerName());
+				for (GCubeGroup userGroup : userGroups) {
+					if (gm.isVRE(userGroup.getGroupId())) {
+						users.addAll(um.listUsersByGroup(userGroup.getGroupId()));
+						_log.debug("getOrganizationUsers added users of group " + userGroup.getGroupId());
+					}
+				}
+			} else { //is a VRE
+				users.addAll(um.listUsersByGroup(currentGroupId));
+				teams = new LiferayRoleManager().listTeamsByGroup(currentGroupId);
+			}
+		} catch (UserManagementSystemException | GroupRetrievalFault | UserRetrievalFault | VirtualGroupNotExistingException e) {
+			e.printStackTrace();
+		}
+		for (GCubeUser user : users) {
+			if (user.getUsername().compareTo("test.user") != 0 && user.getUsername().compareTo(userName) != 0)  { //skip test.user & current user
+				portalBeans.add(new ItemBean(user.getUserId()+"", user.getUsername(), user.getFullname(), user.getUserAvatarURL()));
+			}
+		}
+		for (GCubeTeam gCubeTeam : teams) {
+			portalBeans.add(new ItemBean(gCubeTeam.getTeamId()+"", gCubeTeam.getTeamName()));
+		}
+		_log.trace("Returning " + portalBeans.size() + " users for scope groupid =  " + currentGroupId);
+		return portalBeans;
 	}
 
 	/**