getting cannot merge namespace error while adding b2bpunchout in localextention.xml file.

Getting following error while Adding b2bpunchout in localextension.xml file

 *java.lang.IllegalArgumentException: cannot merge namespace ((lgcfulfilmentprocess)) into ((<merged>)) due to duplicate attribute 'ConsignmentProcess.warehouseConsignmentState(WarehouseConsignmentState):((lgcfulfilmentprocess))::YAttributeDescriptor[lgcfulfilmentprocess-items.xml:35(AttributeTagListener)][PROPERTY]' vs 'ConsignmentProcess.warehouseConsignmentState(WarehouseConsignmentState):((yacceleratorfulfilmentprocess))::YAttributeDescriptor[yacceleratorfulfilmentprocess-items.xml:35(AttributeTagListener)][PROPERTY]'* 

can any one help.

Thanks Sanjeev