Dear Jurgen,
I too checked with the full authorization user id too.
Please try to follow my procedure..
1, create vendor using the transaction code MK01
2, with the same same number create/extend the same to finance via FK01, you will not found the bank information tab.
3, Even I extend the same process via XK01 too, but bank tab is missing.
the second point is my issue
if we process these transactions separate bank information tab will appear
regards,
Sanju M S