Hi Jorg,
Can you execute FM "/SAPSLL/CORE_ADDR_GET" with your Address number as parameter IV_ADRNR_NEW and blank value for iv_nation_new?
Please let us know if you see some values in the result.
I am assuming you haven't changed anything for the standard legal regulation SPLUS?
Basically, I see system is trying to get the data using the above mentioned FM. If not, then system assumes that the partner is not of type 1 - Organisation and starts looking for person address.
Regards
Dhilipan