Created Unassigned: Error evaluating cell [11908]

Hi,
I get an exception "NotImplementedException" when I use EvaluateAllFormulaCells().
The cell creating the error looks like this:
=IF(TYPE(VLOOKUP($A$2;$A$6:$D$21;C5;FALSE))=16;0;VLOOKUP($A$2;$A$6:$D$21;C5;FALSE))

If I remove the TYPE function it works.
When will the TYPE function be implemented?
Also I have searched after a list of which function that is implemented but have not find it.
Could you please give me a list of implemented functions.

I am trying to recalculate a big excel sheet with a lot of stuff.

I am using NPOI 2.0.1 Beta.

Thank you for a great SW!

BR