diff --git a/src/main/java/org/gcube/portal/oidc/lr62/IntraVMJWTCacheProxy.java b/src/main/java/org/gcube/portal/oidc/lr62/IntraVMJWTCacheProxy.java
index 2c287c4..7ffefde 100644
--- a/src/main/java/org/gcube/portal/oidc/lr62/IntraVMJWTCacheProxy.java
+++ b/src/main/java/org/gcube/portal/oidc/lr62/IntraVMJWTCacheProxy.java
@@ -1,6 +1,7 @@
 package org.gcube.portal.oidc.lr62;
 
 import java.util.Collections;
+import java.util.Comparator;
 import java.util.Map;
 import java.util.TreeMap;
 
@@ -12,51 +13,96 @@ import com.liferay.portal.model.User;
 
 public class IntraVMJWTCacheProxy extends JWTCacheProxy {
 
-    private Map<String, String> oidcTokens;
-    private Map<String, String> rptTokens;
+    private Map<User, Map<HttpSession, String>> oidcTokens;
+    private Map<User, Map<HttpSession, String>> rptTokens;
 
     protected IntraVMJWTCacheProxy() {
+        log.info("Initializing tokens caches");
         oidcTokens = Collections.synchronizedMap(new TreeMap<>());
         rptTokens = Collections.synchronizedMap(new TreeMap<>());
     }
 
+    public void checkMap(Map<User, Map<HttpSession, String>> map, User user) {
+        if (!map.containsKey(user)) {
+            log.debug("Initializing map for user: " + user.getScreenName());
+            map.put(user, Collections.synchronizedMap(new TreeMap<>(new Comparator<HttpSession>() {
+                @Override
+                public int compare(HttpSession s1, HttpSession s2) {
+                    return s1.getId().compareTo(s2.getId());
+                }
+            })));
+        }
+    }
+
     @Override
     public void setOIDCToken(User user, HttpSession session, JWTToken token) {
-        oidcTokens.put(generateKey(user, session), JWTTokenUtil.getRawContent(token));
+        checkMap(oidcTokens, user);
+        Map<HttpSession, String> oidcUserMap = oidcTokens.get(user);
+        log.trace("OIDC user's sessions recorded: " + oidcUserMap.keySet().toArray());
+        oidcUserMap.put(session, JWTTokenUtil.getRawContent(token));
     }
 
     @Override
     public void setUMAToken(User user, HttpSession session, JWTToken token) {
-        rptTokens.put(generateKey(user, session), JWTTokenUtil.getRawContent(token));
+        checkMap(rptTokens, user);
+        Map<HttpSession, String> umaUserMap = rptTokens.get(user);
+        log.trace("UMA user's sessions recorded objs: " + umaUserMap.keySet().toArray());
+        umaUserMap.put(session, JWTTokenUtil.getRawContent(token));
     }
 
     @Override
     public JWTToken getOIDCToken(User user, HttpSession session) {
-        return JWTTokenUtil.fromString(oidcTokens.get(generateKey(user, session)));
+        checkMap(oidcTokens, user);
+        log.trace("Getting OIDC token for user '" + user.getScreenName() + "' and session obj: " + session);
+        return JWTTokenUtil.fromString(oidcTokens.get(user).get(session));
     }
 
     @Override
     public JWTToken getUMAToken(User user, HttpSession session) {
-        return JWTTokenUtil.fromString(rptTokens.get(generateKey(user, session)));
+        checkMap(rptTokens, user);
+        log.trace("Getting UMA token for user '" + user.getScreenName() + "' and session obj: " + session);
+        return JWTTokenUtil.fromString(rptTokens.get(user).get(session));
     }
 
     @Override
     public void removeOIDCToken(User user, HttpSession session) {
-        oidcTokens.remove(generateKey(user, session));
+        checkMap(oidcTokens, user);
+        if (oidcTokens.get(user).containsKey(session)) {
+            log.trace("Removing OIDC token for user '" + user.getScreenName() + "' and session obj: " + session);
+            oidcTokens.get(user).remove(session);
+        }
     }
 
     @Override
     public void removeUMAToken(User user, HttpSession session) {
-        rptTokens.remove(generateKey(user, session));
+        checkMap(rptTokens, user);
+        if (rptTokens.get(user).containsKey(session)) {
+            log.trace("Removing UMA token for user '" + user.getScreenName() + "' and session obj: " + session);
+            oidcTokens.get(user).remove(session);
+        }
+    }
+
+    @Override
+    public void removeAllOIDCTokens(User user) {
+        log.trace("Removing OIDC session's tokens of user: " + user.getScreenName());
+        oidcTokens.remove(user);
+    }
+
+    @Override
+    public void removeAllUMATokens(User user) {
+        log.trace("Removing UMA session's tokens of user: " + user.getScreenName());
+        rptTokens.remove(user);
     }
 
     @Override
     public void clearOIDCTokens() {
+        log.trace("Clearing OIDC tokens cache");
         oidcTokens.clear();
     }
 
     @Override
     public void clearUMATokens() {
+        log.trace("Clearing UMA tokens cache");
         rptTokens.clear();
     }