diff --git a/config/alfresco/application-context.xml b/config/alfresco/application-context.xml
index 45531fc7b3..6192cf7e72 100644
--- a/config/alfresco/application-context.xml
+++ b/config/alfresco/application-context.xml
@@ -49,6 +49,11 @@
     <import resource="classpath*:alfresco/patch/*-context.xml" />
     <import resource="classpath*:alfresco/domain/*-context.xml" />
 
+    <!--
+         Import activation extensions for Multi-Tenancy.
+    -->
+    <import resource="classpath*:alfresco/extension/mt/*-context.xml"/>
+    
     <!--
          Import all modules and related components.
          Extensions are explicitly imported after this so that the default
diff --git a/config/alfresco/node-services-context.xml b/config/alfresco/node-services-context.xml
index d309597264..67cbf5329c 100644
--- a/config/alfresco/node-services-context.xml
+++ b/config/alfresco/node-services-context.xml
@@ -42,9 +42,9 @@
       </property>
       <property name="interceptorNames">
          <list>
+            <value>multiTNodeServiceInterceptor</value>
             <value>nodeRefPropertyInterceptor</value>
             <value>mlPropertyInterceptor</value>
-            <value>multiTNodeServiceInterceptor</value>
          </list>
       </property>
    </bean>
diff --git a/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptor.java b/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptor.java
index d65fb0ad0f..3e89483349 100644
--- a/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptor.java
+++ b/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptor.java
@@ -26,6 +26,9 @@ package org.alfresco.repo.tenant;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
 
 import org.alfresco.repo.security.authentication.AuthenticationUtil;
 import org.alfresco.service.cmr.repository.AssociationRef;
@@ -91,218 +94,7 @@ public class MultiTNodeServiceInterceptor extends DelegatingIntroductionIntercep
     {
         this.tenantService = tenantService;
     }
-//    
-//    public void addAspect(NodeRef nodeRef, QName aspectTypeQName, Map<QName, Serializable> aspectProperties) throws InvalidNodeRefException, InvalidAspectException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public ChildAssociationRef addChild(NodeRef parentRef, NodeRef childRef, QName assocTypeQName, QName qname) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<String> cleanup()
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public AssociationRef createAssociation(NodeRef sourceRef, NodeRef targetRef, QName assocTypeQName) throws InvalidNodeRefException, AssociationExistsException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public ChildAssociationRef createNode(NodeRef parentRef, QName assocTypeQName, QName assocQName, QName nodeTypeQName, Map<QName, Serializable> properties)
-//            throws InvalidNodeRefException, InvalidTypeException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public ChildAssociationRef createNode(NodeRef parentRef, QName assocTypeQName, QName assocQName, QName nodeTypeQName) throws InvalidNodeRefException, InvalidTypeException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public StoreRef createStore(String protocol, String identifier) throws StoreExistsException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void deleteNode(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void deleteStore(StoreRef storeRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public boolean exists(NodeRef nodeRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public boolean exists(StoreRef storeRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public Set<QName> getAspects(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<ChildAssociationRef> getChildAssocs(NodeRef nodeRef, QNamePattern typeQNamePattern, QNamePattern qnamePattern) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<ChildAssociationRef> getChildAssocs(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public NodeRef getChildByName(NodeRef nodeRef, QName assocTypeQName, String childName)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public Status getNodeStatus(NodeRef nodeRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<ChildAssociationRef> getParentAssocs(NodeRef nodeRef, QNamePattern typeQNamePattern, QNamePattern qnamePattern) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<ChildAssociationRef> getParentAssocs(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public Path getPath(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<Path> getPaths(NodeRef nodeRef, boolean primaryOnly) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public ChildAssociationRef getPrimaryParent(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public Map<QName, Serializable> getProperties(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public Serializable getProperty(NodeRef nodeRef, QName qname) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public NodeRef getRootNode(StoreRef storeRef) throws InvalidStoreRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<AssociationRef> getSourceAssocs(NodeRef targetRef, QNamePattern qnamePattern) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public NodeRef getStoreArchiveNode(StoreRef storeRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<StoreRef> getStores()
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public List<AssociationRef> getTargetAssocs(NodeRef sourceRef, QNamePattern qnamePattern) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public QName getType(NodeRef nodeRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public boolean hasAspect(NodeRef nodeRef, QName aspectTypeQName) throws InvalidNodeRefException, InvalidAspectException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public ChildAssociationRef moveNode(NodeRef nodeToMoveRef, NodeRef newParentRef, QName assocTypeQName, QName assocQName) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void removeAspect(NodeRef nodeRef, QName aspectTypeQName) throws InvalidNodeRefException, InvalidAspectException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void removeAssociation(NodeRef sourceRef, NodeRef targetRef, QName assocTypeQName) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void removeChild(NodeRef parentRef, NodeRef childRef) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public boolean removeChildAssociation(ChildAssociationRef childAssocRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void removeProperty(NodeRef nodeRef, QName qname) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public boolean removeSeconaryChildAssociation(ChildAssociationRef childAssocRef)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public NodeRef restoreNode(NodeRef archivedNodeRef, NodeRef destinationParentNodeRef, QName assocTypeQName, QName assocQName)
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void setChildAssociationIndex(ChildAssociationRef childAssocRef, int index) throws InvalidChildAssociationRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void setProperties(NodeRef nodeRef, Map<QName, Serializable> properties) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void setProperty(NodeRef nodeRef, QName qname, Serializable value) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
-//    public void setType(NodeRef nodeRef, QName typeQName) throws InvalidNodeRefException
-//    {
-//        throw new UnsupportedOperationException();
-//    }
-//
+    
     @SuppressWarnings("unchecked")
     public Object invoke(MethodInvocation invocation) throws Throwable
     {
@@ -351,6 +143,18 @@ public class MultiTNodeServiceInterceptor extends DelegatingIntroductionIntercep
                 AssociationRef ref = (AssociationRef) arg;
                 newArg = tenantService.getName(ref);
             }
+            
+            if (logger.isDebugEnabled())
+            {
+                if (!EqualsHelper.nullSafeEquals(newArg, arg))
+                {
+                    logger.debug(
+                            "Argument converted: \n" +
+                            "   Before: " + arg + "\n" +
+                            "   After:  " + newArg);
+                }
+            }
+            
             // Substitute the new value
             args[i] = newArg;
         }
@@ -370,7 +174,23 @@ public class MultiTNodeServiceInterceptor extends DelegatingIntroductionIntercep
      */
     private Collection<Object> convertOutboundValues(Collection<Object> rawValues)
     {
-        Collection<Object> convertedValues = new ArrayList<Object>(rawValues.size());
+        /*
+         * Return types can be Lists or Sets, so cater for both.
+         */
+        final Collection<Object> convertedValues;
+        if (rawValues instanceof List)
+        {
+            convertedValues = new ArrayList<Object>(rawValues.size());
+        }
+        else if (rawValues instanceof Set)
+        {
+            convertedValues = new HashSet<Object>(rawValues.size(), 1.0F);
+        }
+        else
+        {
+            throw new IllegalArgumentException("Interceptor can only handle List and Set return types.");
+        }
+        
         for (Object rawValue : rawValues)
         {
             Object convertedValue = convertOutboundValue(rawValue);
diff --git a/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptorTest.java b/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptorTest.java
index f32b709694..d3038056bb 100644
--- a/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptorTest.java
+++ b/source/java/org/alfresco/repo/tenant/MultiTNodeServiceInterceptorTest.java
@@ -29,6 +29,7 @@ import junit.framework.TestCase;
 import org.alfresco.repo.transaction.RetryingTransactionHelper.RetryingTransactionCallback;
 import org.alfresco.service.transaction.TransactionService;
 import org.alfresco.util.ApplicationContextHelper;
+import org.alfresco.util.GUID;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.context.ApplicationContext;
 
@@ -42,7 +43,7 @@ public class MultiTNodeServiceInterceptorTest extends TestCase
 {
     public static ApplicationContext ctx = ApplicationContextHelper.getApplicationContext();
     
-    private String tenant1 = "tenant1";
+    private String tenant1 = "tenant-" + GUID.generate();
     private String tenant1Pwd = "pwd1";
     private boolean enableTest = true;
     private TransactionService transactionService;
diff --git a/source/java/org/alfresco/repo/usage/UserUsageTrackingComponent.java b/source/java/org/alfresco/repo/usage/UserUsageTrackingComponent.java
index 0a9dfbb706..c0be13010b 100644
--- a/source/java/org/alfresco/repo/usage/UserUsageTrackingComponent.java
+++ b/source/java/org/alfresco/repo/usage/UserUsageTrackingComponent.java
@@ -236,6 +236,11 @@ public class UserUsageTrackingComponent
                 
                 for (NodeRef personNodeRef : allPeople)
                 {
+                    // Cater for Lucene indexes being stale
+                    if (!nodeService.exists(personNodeRef))
+                    {
+                        continue;
+                    }
                     Long currentUsage = (Long)nodeService.getProperty(personNodeRef, ContentModel.PROP_SIZE_CURRENT);
                     if (currentUsage == null)
                     {
@@ -361,6 +366,11 @@ public class UserUsageTrackingComponent
             public Object execute() throws Throwable
             {
                 NodeRef personNodeRef = personService.getPerson(username);
+                if (!nodeService.exists(personNodeRef))
+                {
+                    // Ignore
+                    return null;
+                }
                 contentUsageImpl.setUserStoredUsage(personNodeRef, currentUsage);
                 usageService.deleteDeltas(personNodeRef);
                 return null;