strange error (32 512)

I have a very strange problem:
I am writing a perl program that should insert data into a database. It
works perfectly well when starting the script manually. When the
starting the script as cron (same user), it collapses ($fehler = 32 512
which I don't know and can't find).

$fehler=system("psql $new $pguser < $upload/working 2> /dev/null ");

Is there any smarter solution using Perl and what in hell means 32
512???

Hans