Winform客户端引用WCF客户端后，部分类无法正常使用

在项目中用到WCF,项目的结构是这样的：

在SPI项目中编写该解决方案中公共的类及函数；
在WCFService项目中写的是svc文件及WCF服务接口；
在Client中添加WCF服务引用的时候该WCFService项目，然后再UI项目中初始化Client的实例。通过该实例WCFService中的方法。
问题：

有时会出现这么一种情况，在UI中通过初始化Client的实例。通过该实例WCFService中的方法MethodA，该方法的入参是SPI中类ConnectionInfo的实例，然后在UI中再次使用类ConnectionInfo时会发现ConnectionInfo是在Client命名空间下的类，而不是在SPI命名空间下的类。

在WCF自动生成的客户端代理类（Reference.cs文件）中，会将SPI中的类ConnectionInfo，序列化成：

 [System.Diagnostics.DebuggerStepThroughAttribute()]
    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "4.0.0.0")]
    [System.Runtime.Serialization.DataContractAttribute(Name="ConnectionInfo", Namespace="http://schemas.datacontract.org/2004/07/HaiChuang.AMAC.DataSourceSettings.SPI.Mod" +
        "el")]
    [System.SerializableAttribute()]
    public partial class ConnectionInfo : object, System.Runtime.Serialization.IExtensibleDataObject, System.ComponentModel.INotifyPropertyChanged {

        [System.NonSerializedAttribute()]
        private System.Runtime.Serialization.ExtensionDataObject extensionDataField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string ConnectionStringField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string GuidField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string LocationField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string MenuGuidField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string NameField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private string TypeField;

        [System.Runtime.Serialization.OptionalFieldAttribute()]
        private int idField;

        [global::System.ComponentModel.BrowsableAttribute(false)]
        public System.Runtime.Serialization.ExtensionDataObject ExtensionData {
            get {
                return this.extensionDataField;
            }
            set {
                this.extensionDataField = value;
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string ConnectionString {
            get {
                return this.ConnectionStringField;
            }
            set {
                if ((object.ReferenceEquals(this.ConnectionStringField, value) != true)) {
                    this.ConnectionStringField = value;
                    this.RaisePropertyChanged("ConnectionString");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string Guid {
            get {
                return this.GuidField;
            }
            set {
                if ((object.ReferenceEquals(this.GuidField, value) != true)) {
                    this.GuidField = value;
                    this.RaisePropertyChanged("Guid");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string Location {
            get {
                return this.LocationField;
            }
            set {
                if ((object.ReferenceEquals(this.LocationField, value) != true)) {
                    this.LocationField = value;
                    this.RaisePropertyChanged("Location");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string MenuGuid {
            get {
                return this.MenuGuidField;
            }
            set {
                if ((object.ReferenceEquals(this.MenuGuidField, value) != true)) {
                    this.MenuGuidField = value;
                    this.RaisePropertyChanged("MenuGuid");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string Name {
            get {
                return this.NameField;
            }
            set {
                if ((object.ReferenceEquals(this.NameField, value) != true)) {
                    this.NameField = value;
                    this.RaisePropertyChanged("Name");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public string Type {
            get {
                return this.TypeField;
            }
            set {
                if ((object.ReferenceEquals(this.TypeField, value) != true)) {
                    this.TypeField = value;
                    this.RaisePropertyChanged("Type");
                }
            }
        }

        [System.Runtime.Serialization.DataMemberAttribute()]
        public int id {
            get {
                return this.idField;
            }
            set {
                if ((this.idField.Equals(value) != true)) {
                    this.idField = value;
                    this.RaisePropertyChanged("id");
                }
            }
        }

        public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;

        protected void RaisePropertyChanged(string propertyName) {
            System.ComponentModel.PropertyChangedEventHandler propertyChanged = this.PropertyChanged;
            if ((propertyChanged != null)) {
                propertyChanged(this, new System.ComponentModel.PropertyChangedEventArgs(propertyName));
            }
        }
    }

该实体类代码为：

/// <summary>
    /// 数据源信息
    /// </summary>
    public class ConnectionInfo
    {
        public int id { get; set; }
        public string Guid { get; set; }
        public string Name { get; set; }
        public string Location { get; set; }
        public string Type { get; set; }
        public string ConnectionString { get; set; }
        public string MenuGuid { get; set; }

    }

在 CLient项目的wcf引用上右键，可以看到该实体类