diff --git a/source/java/org/alfresco/repo/attributes/PropTablesCleaner.java b/source/java/org/alfresco/repo/attributes/PropTablesCleaner.java
index 5fb07672df..be0fb8f666 100644
--- a/source/java/org/alfresco/repo/attributes/PropTablesCleaner.java
+++ b/source/java/org/alfresco/repo/attributes/PropTablesCleaner.java
@@ -23,7 +23,6 @@ import org.alfresco.repo.lock.JobLockService;
 import org.alfresco.repo.lock.LockAcquisitionException;
 import org.alfresco.service.namespace.NamespaceService;
 import org.alfresco.service.namespace.QName;
-import org.alfresco.util.Pair;
 import org.alfresco.util.PropertyCheck;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -39,18 +38,11 @@ public class PropTablesCleaner
     private JobLockService jobLockService;
 
     /* 1 minute */
-    private static final long LOCK_TTL = 60000L;
+    private static final long LOCK_TTL = 360000L;
     private static final QName LOCK_QNAME = QName.createQName(NamespaceService.SYSTEM_MODEL_1_0_URI, PropTablesCleaner.class.getName());
-    private static ThreadLocal<Pair<Long, String>> lockThreadLocal = new ThreadLocal<Pair<Long, String>>();
 
     private static Log logger = LogFactory.getLog(PropTablesCleaner.class);
 
-    public void checkProperties()
-    {
-        PropertyCheck.mandatory(this, "jobLockService", jobLockService);
-        PropertyCheck.mandatory(this, "propertyValueDAO", propertyValueDAO);
-    }
-
     public void setPropertyValueDAO(PropertyValueDAO propertyValueDAO)
     {
         this.propertyValueDAO = propertyValueDAO;
@@ -61,76 +53,47 @@ public class PropTablesCleaner
         this.jobLockService = jobLockService;
     }
 
-    /**
-     * Lazily update the job lock
-     */
-    private void refreshLock()
+    public void checkProperties()
     {
-        Pair<Long, String> lockPair = lockThreadLocal.get();
-        if (lockPair == null)
-        {
-            String lockToken = jobLockService.getLock(LOCK_QNAME, LOCK_TTL);
-            Long lastLock = new Long(System.currentTimeMillis());
-            // We have not locked before
-            lockPair = new Pair<Long, String>(lastLock, lockToken);
-            lockThreadLocal.set(lockPair);
-        }
-        else
-        {
-            long now = System.currentTimeMillis();
-            long lastLock = lockPair.getFirst().longValue();
-            String lockToken = lockPair.getSecond();
-            // Only refresh the lock if we are past a threshold
-            if (now - lastLock > (long)(LOCK_TTL/2L))
-            {
-                jobLockService.refreshLock(lockToken, LOCK_QNAME, LOCK_TTL);
-                lastLock = System.currentTimeMillis();
-                lockPair = new Pair<Long, String>(lastLock, lockToken);
-                lockThreadLocal.set(lockPair);
-            }
-        }
+        PropertyCheck.mandatory(this, "jobLockService", jobLockService);
+        PropertyCheck.mandatory(this, "propertyValueDAO", propertyValueDAO);
     }
 
     /**
-     * Release the lock after the job completes
+     * Get {@link #LOCK_QNAME a lock} for {@link #LOCK_TTL a long-running job} and {@link PropertyValueDAO#cleanupUnusedValues() call through}
+     * to get the unused data cleaned up.
      */
-    private void releaseLock()
-    {
-        Pair<Long, String> lockPair = lockThreadLocal.get();
-        if (lockPair != null)
-        {
-            // We can't release without a token
-            try
-            {
-                jobLockService.releaseLock(lockPair.getSecond(), LOCK_QNAME);
-            }
-            finally
-            {
-                // Reset
-                lockThreadLocal.set(null);
-            }
-        }
-        // else: We can't release without a token
-    }
-
     public void execute()
     {
         checkProperties();
+        
+        String lockToken = null;
         try
         {
-            refreshLock();
+            // Get a lock
+            lockToken = jobLockService.getLock(LOCK_QNAME, LOCK_TTL);
             propertyValueDAO.cleanupUnusedValues();
         }
         catch (LockAcquisitionException e)
         {
             if (logger.isDebugEnabled())
             {
-                logger.debug("Skipping prop tables cleaning.  " + e.getMessage());
+                logger.debug("Skipping prop tables cleaning (could not get lock): " + e.getMessage());
             }
         }
         finally
         {
-            releaseLock();
+            if (lockToken != null)
+            {
+                try
+                {
+                    jobLockService.releaseLock(lockToken, LOCK_QNAME);
+                }
+                catch (LockAcquisitionException e)
+                {
+                    // Ignore
+                }
+            }
         }
     }
 }
diff --git a/source/java/org/alfresco/repo/attributes/PropTablesCleanupJob.java b/source/java/org/alfresco/repo/attributes/PropTablesCleanupJob.java
index aabd672c39..9ea483383c 100644
--- a/source/java/org/alfresco/repo/attributes/PropTablesCleanupJob.java
+++ b/source/java/org/alfresco/repo/attributes/PropTablesCleanupJob.java
@@ -19,9 +19,6 @@
 package org.alfresco.repo.attributes;
 
 import org.alfresco.error.AlfrescoRuntimeException;
-import org.alfresco.repo.domain.propval.PropertyValueDAO;
-import org.alfresco.repo.lock.JobLockService;
-import org.alfresco.repo.lock.LockAcquisitionException;
 import org.quartz.Job;
 import org.quartz.JobDataMap;
 import org.quartz.JobExecutionContext;