I have a WPF application running with VS2010 .Net3.5 using Nhibernate with FluentNHibernate + SQLite, and all works fine.
Now I want to change to use .Net4, but thi
I had a similar problem with NH, VS2010, .Net4, but with the Oracle ODP.Net drivers and 32bit.
The solution was to declare a "qualified assembly" in the web.config file with an explicit version number. See my summary.
Maybe this solution applies to your problem as well.