PRE-PACKING-SFC Site level hook does not fire after upgrade

Hi,

I have upgraded a test system recently to 6.0.4.18. When testing the packing module I don't get any
response from a PRE-PACKING-SFC hook I have on site level.

My hook normally does a document print (Loftware) for a packing label. I have a production system running
6.0.4.12 where this is working perfectly. 

After checking all patches from 6.0.4.12 to 6.0.4.18 I find that in patch 13 and 15 it is a reference to SAP Note: 1918153
explaining some dto changes for PRE-PACKING-SFC and PACK-VALIDATION hooks.

Can this in any way relate to the troubles I am having?

Best Regards,

Johan Nordebrink