泛型 序化反序化问题，高手请赐教

我用的对象实体 泛型的使用率比较高，不过泛型序化反序化出错请高手赐教。
对象实体using System;
using System.Collections.Generic;
using System.Text;
using System.Xml.Serialization;namespace xmlXuLieHua
{
    /// <summary>
    /// xml 序列化与反序列化
    /// chenxun 2009年3月18日10:35:53   对象
    /// </summary>
    [Serializable, XmlRoot(Namespace = "http://yunge.com")]
    public class Students
    {        private IList<Student> _Student;
        [System.Xml.Serialization.XmlElementAttribute("Student")]
        public IList<Student> Student
        {
            set { _Student = value; }
            get { return _Student; }
        }
    }    [Serializable, XmlRoot(Namespace = "http://yunge.com")]
    public class Student
    {
        private long _Number;
        private string _Name;
        private bool _enabled;        public IList<Dorm> _dorm;        public long Number
        {
            set { _Number = value; }
            get { return _Number; }
        }
        public string Name
        {
            set { _Name = value; }
            get { return _Name; }
        }        public bool Enabled
        {
            set { _enabled=value;}
            get{return _enabled;}
        }        [System.Xml.Serialization.XmlElementAttribute("dorm")]
        public IList<Dorm> Dorm
        {
            set { _dorm = value; }
            get { return _dorm; }
        }    }    [Serializable, XmlRoot(Namespace = "http://yunge.com")]
    public class Dorm
    {
        private string _Name;
        private string _Number;        public string Name
        {
            get { return _Name; }
            set { _Name = value; }
        }        public string Number
        {
            get { return _Number; }
            set { _Number = value; }
        }
    }
}xml 格式<?xml version="1.0"?>
<Students xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://yunge.com">
  <Student>
    <Number>222222</Number>
    <Name>2222</Name>
    <enabled>true</enabled>
    <dorm>
      <Name>222</Name>
      <Number>22-22-2</Number>
    </dorm>
    <dorm>
      <Name>222</Name>
      <Number>22-222-2</Number>
    </dorm>
  </Student>
  <Student>
    <Number>333333</Number>
    <Name>3333333333</Name>
    <enabled>false</enabled>
    <dorm>
      <Name>333333</Name>
      <Number>33-333-3</Number>
    </dorm>
    <dorm>
      <Name>3333</Name>
      <Number>33-3333-333</Number>
    </dorm>
  </Student>
</Students>