MDPV can't set characteristic VBAP-MATNR as irrelevant

Hi

I have a configurable material which has a characteristic based on VBAP-MATNR for class type 300 (configuration). I use that dummy characteristic in Variant tables and constraints in tx PMEVC...

I have also set the relevant characteristics for variant matching in tx MDPV.

But for some reason that characteristic for the material can't be excluded for variant matching, henceforth my variant matching does not deliver a result when i try to find a material variant during configuration in a sales order, since the material number of the configurable never matches the material number of the variant...

If i remove the characteristic for the material from the class it all works fine!

Any ideas? Is there a way to use the sales item material number VBAP-MATNR in dependencies without having to define a dummy characteristic for it?

Thank you!

Bjorn