Modify group through REST CLIENT fails.

URL-

http://localhost:8080/restconf/config/opendaylight-inventory:nodes/node/openflow:1/group/1

Request body

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<group xmlns="urn:opendaylight:flow:inventory">
    <group-name>Foo</group-name>
    <buckets>
        <bucket>
            <action>
                <pop-vlan-action/>
                <order>0</order>
            </action>
            <bucket-id>12</bucket-id>
            <watch_group>14</watch_group>
            <watch_port>1234</watch_port>
            <weight>50</weight>
        </bucket>
    </buckets>
    <barrier>false</barrier>
    <group-id>1</group-id>
    <group-type>group-select</group-type>
</group>

Response headers-

500 Internal Server Error

Logs in controller-

inventory.rev130819.node.NodeConnector[key=NodeConnectorKey [_id=Uri [_value=openflow:1:4294967294]]]]]], _ingress=null, _payload=[1, -128, -62, 0, 0, 14, 0, 0, 0, 0, 0, 1, -120, -52, 2, 7, 4, 0, 0, 0, 0, 0, 1, 4, 9, 7, 102, 102, 102, 102, 102, 102, 102, 101, 6, 2, 0, 120, 10, 10, 111, 112, 101, 110, 102, 108, 111, 119, 58, 49, -2, 25, 0, 38, -31, 0, 111, 112, 101, 110, 102, 108, 111, 119, 58, 49, 58, 52, 50, 57, 52, 57, 54, 55, 50, 57, 52, 0, 0], _node=NodeRef [_value=InstanceIdentifier [path=[org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.Nodes, org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.nodes.Node[key=NodeKey [_id=Uri [_value=openflow:1]]]]]], augmentation=[]]
2014-01-24 16:13:31.187 IST [pool-23-thread-4] ERROR o.o.c.m.s.c.i.service.TwoPhaseCommit - Transaction: DOM-7941 Request Commit failed
java.lang.IllegalArgumentException: null
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:76) ~[bundlefile:na]
at org.opendaylight.yangtools.yang.util.YangDataOperations.mergeContainer(YangDataOperations.java:137) ~[na:na]
at org.opendaylight.yangtools.yang.util.YangDataOperations.merge(YangDataOperations.java:42) ~[na:na]
at org.opendaylight.controller.sal.dom.broker.impl.SchemaAwareDataStoreAdapter.mergeData(SchemaAwareDataStoreAdapter.java:159) ~[na:na]
at org.opendaylight.controller.sal.dom.broker.impl.SchemaAwareDataStoreAdapter$NormalizedDataModification.mergeConfigurationData(SchemaAwareDataStoreAdapter.java:318) ~[na:na]
at org.opendaylight.controller.sal.dom.broker.impl.SchemaAwareDataStoreAdapter$NormalizedDataModification.mergeConfigurationData(SchemaAwareDataStoreAdapter.java:289) ~[na:na]
at org.opendaylight.controller.md.sal.common.impl.AbstractDataModification.putConfigurationData(AbstractDataModification.java:70) ~[bundlefile:na]
at org.opendaylight.controller.sal.dom.broker.impl.SchemaAwareDataStoreAdapter.prepareMergedTransaction(SchemaAwareDataStoreAdapter.java:176) ~[na:na]
at org.opendaylight.controller.sal.dom.broker.impl.SchemaAwareDataStoreAdapter.requestCommit(SchemaAwareDataStoreAdapter.java:115) ~[na:na]
at org.opendaylight.controller.md.sal.common.impl.service.TwoPhaseCommit.call(TwoPhaseCommit.java:76) [bundlefile:na]
at org.opendaylight.controller.md.sal.common.impl.service.TwoPhaseCommit.call(TwoPhaseCommit.java:31) [bundlefile:na]
at java.util.concurrent.FutureTask.run(FutureTask.java:262) [na:1.7.0_45]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [na:1.7.0_45]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [na:1.7.0_45]
at java.lang.Thread.run(Thread.java:744) [na:1.7.0_45]
2014-01-24 16:13:34.595 IST [Timer-4] INFO o.o.o.o.m.c.s.ModelDrivenSwitchImpl - TransmitPacket - TransmitPacketInput [_cookie=null, _egress=NodeConnectorRef [_value=InstanceIdentifier [path=[org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.Nodes, org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.nodes.Node[key=NodeKey [_id=Uri [_value=openflow:1]]], org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.node.NodeConnector[key=NodeConnectorKey [_id=Uri [_value=openflow:1:1]]]]]], _ingress=null, _payload=[1, -128, -62, 0, 0, 14, -46, -106, -13, -101, -38, 113, -120, -52, 2, 7, 4, 0, 0, 0, 0, 0, 1, 4, 2, 7, 49, 6, 2, 0, 120, 10, 10, 111, 112, 101, 110, 102, 108, 111, 119, 58, 49, -2, 16, 0, 38, -31, 0, 111, 112, 101, 110, 102, 108, 111, 119, 58, 49, 58, 49, 0, 0], _node=NodeRef [_value=InstanceIdentifier [path=[org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.Nodes, org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.nodes.Node[key=NodeKey [_id=Uri [_value=openflow:1]]]]]], augmentation=[]]
2014-01-24 16:13:34.596 IST [Timer-4] INFO o.o.o.o.m.c.s.ModelDrivenSwitchImpl - TransmitPacket - TransmitPacketInput [_cookie=null, _egress=NodeConnectorRef [_value=InstanceIdentifier [path=[org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.Nodes, org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.nodes.Node[key=NodeKey [_id=Uri [_value=openflow:1]]], org.opendaylight.yang.gen.v1.urn.opendaylight.inventory.rev130819.node.NodeConnector[key=NodeConnectorKey [_id=Uri [_value=openflow:1:4294967294]]]]]], _ingress=null, _payload=[1, -128, -62, 0, 0, 14, 0, 0, 0, 0, 0, 1, -120, -52, 2, 7, 4, 0, 0, 0, 0, 0, 1, 4, 9, 7, 102, 102, 102, 102, 102, 102, 102, 101, 6, 2, 0, 120, 10, 10, 111, 112, 101, 110, 102, 108, 111, 119, 58, 49, -2, 25, 0, 38, -31, 0, 111, 112, 101, 110, 102, 108