new AM, build returns error

Hi,

my new AM starts working..., calling something like

CREATE INDEX idx ON films USING ebi (did)

returns now:

ERROR: unexpected EBI relation size: 3, should be 4294967295

The second argument looks for me like max uint32... there might be
somehting wrong here I think? Is there somehting wrong with:

estimate_rel_size(heap, NULL, &relpages, &reltuples);

The state is passed to the build callback again and again... and
result->heap_tuples = reltuples; takes the estimated number of tuples.
Where is the error?

I know that this is a rather complicated question, due to no source code.

Greetz, Yves