Mono "NetDataContractSerializer.Serialize"

I'm getting following exception

System.NotImplementedException: The requested feature is not implemented.
    开发者_运维百科  at System.Runtime.Serialization.NetDataContractSerializer.WriteStartObject (System.Xml.XmlDictionaryWriter writer, System.Object graph) [0x00000] in <filename unknown>:0 
      at System.Runtime.Serialization.XmlObjectSerializer.WriteObject (System.Xml.XmlDictionaryWriter writer, System.Object graph) [0x00000] in <filename unknown>:0 
      at System.Runtime.Serialization.XmlObjectSerializer.WriteObject (System.Xml.XmlWriter writer, System.Object graph) [0x00000] in <filename unknown>:0 
      at System.Runtime.Serialization.NetDataContractSerializer.Serialize (System.IO.Stream stream, System.Object graph) [0x00000] in <filename unknown>:0 
      at BinaryAnalysis.Data.ContractContainer.ContractContainerEntity.SetValue (System.Object val) [0x00000] in <filename unknown>:0 

When I try to serialize my Pono using NetDataContractSerializer using Mono 2.10.2-5. There are no information about roadmap of theese classes in mono. Any workarounds for that?