银行转账程序

写了一个转账的程序，本希望能利用MTS的事务来处理一些事情，结果不对。
大家帮我看看错在哪里。

using System;
using System.Data;
using System.Data.SqlClient;
using System.Diagnostics;
using System.EnterpriseServices;

using Meyer.Utility;

namespace Meyer.Component
{

 [Transaction(TransactionOption.Required)]
 public class Account:ServicedComponent
 {
  private int _id;
  private decimal _amount;

  public Account()
  {
  }

  public void Set(int id, decimal amount)
  {
   _id = id;
   _amount = amount;
  }

  private void UpdateAmount(decimal amount)
  {
   const string update = "UPDATE Account SET Amount = @Amount WHERE ID = @ID";

   SqlParameter[] parm = new SqlParameter[]{
              new SqlParameter("@Amount", SqlDbType.Decimal),
              new SqlParameter("@ID", SqlDbType.Int)
             };
   
   parm[0].Value = amount;
   parm[1].Value = _id;

   Database.ExecuteNonQuery(CommandType.Text, update, parm);   
  }

  [AutoComplete(true)]
  public void Deposit(decimal amount)
  {
   try
   {
    UpdateAmount(_amount + amount);
   }
   catch
   {
    throw;
   }
  }

  [AutoComplete(true)]
  public void Withdraw(decimal amount)
  {
   try
   {
    UpdateAmount(_amount - amount);

    if (amount > _amount)
    {
     throw new Exception("余额不足");
    }                    
   }
   catch
   {
    throw;
   }
  }

  [AutoComplete(true)]
  public void TransferFunds(Account destination, decimal amount)
  {
   try
   {
    destination.Deposit(amount);
    Withdraw(amount);   
   }
   catch
   {
    throw;
   }
  }
 }
}

MainClass.cs

using System;
using Meyer.Component;

namespace Transfer
{
 /// <summary>
 /// MainClass 的摘要说明。
 /// </summary>
 public class MainClass
 {
  static void Main()
  {
   try
   {
    Account from = new Account();
    from.Set(1, 150);

    Account to = new Account();
    to.Set(2, 200);

    from.TransferFunds(to, 200);
   }
   catch(Exception exp)
   {
    Console.Write(exp.Message);
   }
  }
 }
}