Handling Transactions in DAO with an Injected iBATIS.NET SQL Mapper

I am currently using iBATIS.NET for a small application I am building. I like to create concrete Classes for my DAOs instead of using ISqlMapper directly and invoking named SQL statements. I am not using a Dependency Injection container of any sort, so ideally I have my DAOs set up as follows:

public abstract class AbstractDAO
{
    /// <summary>
    /// SQL Mapper.
    /// </summary>
    ISqlMapper mapper;

    /// <summary>
    /// Default Constructor.
    /// </summary>
    /// <param name="mapper"></param>
    public AbstractDAO(ISqlMapper mapper)
    {
        this.mapper = mapper;
    }
}

public class NodeDAO : AbstractDAO
{
    /// <summary>
    /// Default Constructor.
    /// </summary>
    /// <param name="mapper"></param>
    public NodeDAO(ISqlMapper mapper) : base(mapper) { }

    /// <summary>开发者_如何学C;
    /// Insert Node.
    /// </summary>
    /// <param name="node"></param>
    public void InsertNode(Node node)
    {
        // ... Assume Some Pretty Code.
    }
}

public class NodeRevisionDAO : AbstractDAO
{
    /// <summary>
    /// Default Constructor.
    /// </summary>
    /// <param name="mapper"></param>
    public NodeRevisionDAO (ISqlMapper mapper) : base(mapper) { }

    /// <summary>
    /// Insert Node Revision.
    /// </summary>
    /// <param name="nodeRevision"></param>
    public void InsertNodeRevision(NodeRevision nodeRevision)
    {
        // ... Assume Some Pretty Code.
    }
}

From my main application code, let's say in some form of Business Layer, I would ideally call two insert Methods on the DAOs:

// ... Assume DAOs are Initialized.
nodeDAO.InsertNode(node);
nodeRevisionDAO.InsertNodeRevision(nodeRevision);

I want to make sure both statements are executed as an atomic operation in a transaction so that if either fails, both will be rolled back. But because the ISqlMapper is injected in both DAOs I have no control over the transactions.

What would be the best approach to this problem? Putting it in another way, how can I handle transactions without exposing the ISqlMapper?