Bad breaks with Tbl width expand

Hello there,

I created the PDF using t.lout (in attachment) with:

lout t.lout | ps2pdf - > t.pdf

And the resulting PDF shows the text doing unnecessary breaks (as seen in
attachment).

Removing width{expand} would fix it but I need it in order to keep the
table width expanded if a cell contains less text.

Is it a bug?

Thank you,
Robin