diff --git a/api/src/com/cloud/agent/api/SecurityIngressRulesCmd.java b/api/src/com/cloud/agent/api/SecurityIngressRulesCmd.java
index 9c2589b97b8..97adc3aa74a 100644
--- a/api/src/com/cloud/agent/api/SecurityIngressRulesCmd.java
+++ b/api/src/com/cloud/agent/api/SecurityIngressRulesCmd.java
@@ -17,6 +17,8 @@
  */
 package com.cloud.agent.api;
 
+import org.apache.commons.codec.digest.DigestUtils;
+
 import com.cloud.agent.api.LogLevel.Log4jLevel;
 
 
@@ -84,6 +86,10 @@ public class SecurityIngressRulesCmd extends Command {
         this.signature = signature;
         this.seqNum = seqNum;
         this.vmId  = vmId;
+        if (signature == null) {
+            String stringified = stringifyRules();
+            this.signature = DigestUtils.md5Hex(stringified);
+        }
     }
 
 
diff --git a/server/src/com/cloud/network/security/SecurityGroupManagerImpl2.java b/server/src/com/cloud/network/security/SecurityGroupManagerImpl2.java
index 3df6371f69c..c02783fe0a6 100644
--- a/server/src/com/cloud/network/security/SecurityGroupManagerImpl2.java
+++ b/server/src/com/cloud/network/security/SecurityGroupManagerImpl2.java
@@ -88,6 +88,7 @@ public class SecurityGroupManagerImpl2 extends SecurityGroupManagerImpl {
         }
         Set<Long> workItems = new TreeSet<Long>();
         workItems.addAll(affectedVms);
+        
         if (s_logger.isTraceEnabled()) {
             s_logger.trace("Security Group Mgr v2: scheduling ruleset updates for " + affectedVms.size() + " vms " + " (unique=" + workItems.size() + "), current queue size=" + _workQueue.size());
         }
@@ -158,11 +159,11 @@ public class SecurityGroupManagerImpl2 extends SecurityGroupManagerImpl {
             Long agentId = vm.getHostId();
             if (agentId != null) {
                 SecurityIngressRulesCmd cmd = generateRulesetCmd(vm.getInstanceName(), vm.getPrivateIpAddress(), 
-                        vm.getPrivateMacAddress(), vm.getId(), generateRulesetSignature(rules), 
+                        vm.getPrivateMacAddress(), vm.getId(), null, 
                         work.getLogsequenceNumber(), rules);
                 if (s_logger.isTraceEnabled()) {
                     s_logger.trace("SecurityGroupManager v2: sending ruleset update for vm " + vm.getInstanceName() + 
-                                   ": num rules=" + cmd.getRuleSet().length + " num cidrs=" + cmd.getTotalNumCidrs());
+                                   ": num rules=" + cmd.getRuleSet().length + " num cidrs=" + cmd.getTotalNumCidrs() + " sig=" + cmd.getSignature());
                 }
                 Commands cmds = new Commands(cmd);
                 try {