Hi, Ive been reading about this infamous problem and need some advice :

From what ive been reading there are several options :

1. Use the nhibernate nullables library
(wouldnt this mean I need to install hibernate onto the client machines?, also tying my application to use nhibernate and a non .Net data type)

2. Use .NET 2.0 (not an option)

3. Hack and change the source code to search for Minvalue manually.
(rather not)

Has anyone written anything that does not rely on hibernate libraries that can solve this problem? I would not like to change all my mappings if i can avoid it.

Are you sure you will need to deploy NHibernate.dll to client if you use Nullables.dll library? I've looked at Nullables.dll with ildasm and I can't see reference to NHibernate. ( Nullables.NHibernate.dll has dependency on NHibernate but this one is only needed where your DAL lies, isn't it ?)

I have VERY bad experience with hack-solution with DateTime.MinValue ( it confuses NH dirty checker resulting in continuous UPDATE commands)

So I recommend Nullables - personally didn't used it without NH but I'm guessing that it will work.

You can implement a custom type (see IUserType interface) which will convert between DateTime.MinValue and NULL.

thanks guys, ill credit you both, I was going to implement the hack until i get time to write a more decent solution but looks like ill spend time looking into custom types.

Can we expect this to be addressed in a future version of nhibernate? Or is it considered a .Net DateTime problem.

As far as I know, support for .NET 2.0 Nullable<> is being added right now.