diff --git a/pom.xml b/pom.xml
index 70e2661b85..d4d1555d41 100644
--- a/pom.xml
+++ b/pom.xml
@@ -182,6 +182,10 @@
                     <groupId>org.springframework</groupId>
                     <artifactId>spring-aop</artifactId>
                 </exclusion>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-expression</artifactId>
+                </exclusion>
                 <exclusion>
                     <groupId>org.hibernate</groupId>
                     <artifactId>hibernate</artifactId>
@@ -645,7 +649,13 @@
         <dependency>
             <groupId>org.springframework.security</groupId>
             <artifactId>spring-security-core</artifactId>
-            <version>3.1.0.RELEASE</version>
+            <version>3.1.3.RELEASE</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-expression</artifactId>
+                </exclusion>
+            </exclusions>
         </dependency>
         <dependency>
             <groupId>org.springframework.social</groupId>
diff --git a/source/java/org/alfresco/repo/management/DynamicMBeanExporter.java b/source/java/org/alfresco/repo/management/DynamicMBeanExporter.java
index 4ce35b6993..27aeb310c8 100644
--- a/source/java/org/alfresco/repo/management/DynamicMBeanExporter.java
+++ b/source/java/org/alfresco/repo/management/DynamicMBeanExporter.java
@@ -7,7 +7,6 @@
  */
 package org.alfresco.repo.management;
 
-import javax.management.InstanceAlreadyExistsException;
 import javax.management.JMException;
 import javax.management.MBeanServer;
 import javax.management.ObjectName;
@@ -53,18 +52,7 @@ public class DynamicMBeanExporter extends MBeanExporter implements DynamicMBeanE
      */
     public void unregisterMBean(ObjectName objectName)
     {
-        if (this.registeredBeans.remove(objectName))
-        {
-            try
-            {
-                this.server.unregisterMBean(objectName);
-                onUnregister(objectName);
-            }
-            catch (JMException e)
-            {
-                throw new RuntimeException(e);
-            }
-        }
+        doUnregister(objectName);
     }
 
     /*
@@ -87,22 +75,12 @@ public class DynamicMBeanExporter extends MBeanExporter implements DynamicMBeanE
         ObjectName actualObjectName = objectName;
         try
         {
-            try
-            {
-                actualObjectName = this.server.registerMBean(mbean, objectName).getObjectName();
-            }
-            catch (InstanceAlreadyExistsException ex)
-            {
-                this.server.unregisterMBean(objectName);
-                actualObjectName = this.server.registerMBean(mbean, objectName).getObjectName();
-            }
+            doRegister(mbean, actualObjectName);
         }
         catch (JMException e)
         {
             throw new RuntimeException(e);
         }
-        this.registeredBeans.add(actualObjectName);
-        onRegister(actualObjectName);
         return actualObjectName;
     }
 }
\ No newline at end of file