from the moment we've migrated from hibernate 2 to hibernate3 ,around 30% of queries can not execute anymore,while there were not any problem with the previous version. does anybody have such problems?

for example some of errors we see r like these

Specified cast is not valid:

 Repository<CountrySubdivision>.Find(p => p.Parent.Id == parentId);

specified method is not supported:

 public JsonResult AllEducationDegree(string search)
{
    var data = Repository<EducationDegree>
      .FindBySpecification(new EducationDegreeSpecification().Search(search))
      .Take(10)
      .Select(p => new NameValue(p.Title, (int)p.Id))
      .ToList();
     // .AsDropdown(" ");
    return Json(data, JsonRequestBehavior.AllowGet);
}

   public class EducationDegreeSpecification : FluentSpecification<EducationDegree>
   {
     public EducationDegreeSpecification Search(string EducationDegreeSearch)
      {
      if (!String.IsNullOrEmpty(EducationDegreeSearch))
      {
        string[] searchs = EducationDegreeSearch.Split(' ');
        foreach (string search in searchs)
        {
            if (!String.IsNullOrEmpty(search))
            {
                AddExpression(p => p.Title.Contains(search));
            }
        }
    }
    return this;
}

}