Why do lambda expressions in VB differ from C#?

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I just came across a bug in NHibernate which happens to already be raised: https://nhibernate.jira.com/browse/NH-2763

I'm not sure if this applies to anything else other than enums but when using a Lambda from VB, it looks different to the same Lambda from C#.

C#:

Where(x => x.Status == EmployeeStatus.Active)

VB

Where(Function(x) x.Status = EmployeeStatus.Active)

They are the same as far as I'm aware? (My VB isn't great)

If I put a break point on the same line of code, where the above code is passed into. In C# I get:

C# version

On the same line when VB version is passed in, I get:

VB version

Is this something I'm doing wrong? Is the result's the same, just displayed different between C#/VB?

Edit: Ok so they are displayed different, but they can't be the same because NHibernate cannot handle it. The C# version is handled perfectly fine by NHibernate, the VB version resolves in the following exception being thrown:

Exception

The NHibernate StackTrace:

   at NHibernate.Impl.ExpressionProcessor.FindMemberExpression(Expression expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 168
   at NHibernate.Impl.ExpressionProcessor.ProcessSimpleExpression(Expression left, Expression right, ExpressionType nodeType) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 323
   at NHibernate.Impl.ExpressionProcessor.ProcessSimpleExpression(BinaryExpression be) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 316
   at NHibernate.Impl.ExpressionProcessor.ProcessBinaryExpression(BinaryExpression expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 418
   at NHibernate.Impl.ExpressionProcessor.ProcessExpression(Expression expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 486
   at NHibernate.Impl.ExpressionProcessor.ProcessExpression[T](Expression`1 expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Impl\ExpressionProcessor.cs:line 504
   at NHibernate.Criterion.QueryOver`2.Add(Expression`1 expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Criterion\QueryOver.cs:line 635
   at NHibernate.Criterion.QueryOver`2.NHibernate.IQueryOver<TRoot,TSubType>.Where(Expression`1 expression) in d:\CSharp\NH\NH\nhibernate\src\NHibernate\Criterion\QueryOver.cs:line 686
   at *removed*.EmployeeRepository.GetByEntityId(Int64 entityId, Expression`1 basicCriteria) in D:\*removed*\EmployeeRepository.cs:line 76

So something must be different between the two?

Edit 2:

For Jonathan. This is the method where the expression is used:

public IEnumerable<Employee> GetByEntityId(long entityId, Expression<Func<Employee, bool>> basicCriteria)
{
    IEnumerable<Employee> result;

    using (var tx = Session.BeginTransaction())
    {
        var employeeQuery = Session.QueryOver<Employee>()
                                    .Where(x => x.EntityId == entityId);

        if (basicCriteria != null)
            employeeQuery = employeeQuery.Where(basicCriteria);

        result = employeeQuery.List();

        tx.Commit();
    }

    return result;
}
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