Classification of object links from DRAW to DRAW?

Hi,

I want to use classification for object links between DMS documets.

Classification for object links between DMS document and vendor works.

But - for object links between DMS and DMS it doesn't work.

I checked the "Additional functions" for this object link type in SPRO - but the button for classification doesn't appear.

- What can be false?

- Could it be possible, that object links between documents cannot be classified?

- If it is possible, to classifiy the object links - which function modules can I use to set/read the classification?

Thanks

Roland