vif hotplug fix

diff --git a/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java b/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java
index 007cd28..9385e3a 100755
--- a/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java
+++ b/plugins/hypervisors/kvm/src/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java
@@ -1250,12 +1250,12 @@ public class LibvirtComputingResource extends ServerResourceBase implements
                 if (nic.getBrName().equalsIgnoreCase(_linkLocalBridgeName)) {
                     vlanAllocatedToVM.put("LinkLocal", nicPos);
                 } else {
-                    String vlanId = getVlanIdFromBridge(nic.getBrName());
-                    if (vlanId != null) {
-                        vlanAllocatedToVM.put(vlanId, nicPos);
-                    } else {
-                        vlanAllocatedToVM.put(Vlan.UNTAGGED, nicPos);
-                    }
+                       if (nic.getBrName().equalsIgnoreCase(_publicBridgeName) || nic.getBrName().equalsIgnoreCase(_privBridgeName) || nic.getBrName().equalsIgnoreCase(_guestBridgeName)) {
+                               vlanAllocatedToVM.put(Vlan.UNTAGGED, nicPos);
+                       } else {
+                               String vlanId = getVlanIdFromBridge(nic.getBrName());
+                               vlanAllocatedToVM.put(vlanId, nicPos);
+                       }
                 }
                 nicPos++;
             }