[GRASSLIST:8732] v.in.ogr layer not available

Hello,
I exported tables to Postgres/Postgis and I can reimport / link this
tables with v.in.ogr.

But if I copy these tables in Postgres with the same structure, I can't
link them to GRASS

v.in.ogr says "layer ... not available". The other tables appear in the
list of layers.

What am I doing wrong?

Tim