cluster crash or error Duplicate entry '' for key 65

[Pierre COLOMBIER]

I'm trying to move a big database to ndb cluster
(my source file is an sql dump)

my cluster is configured with 1adm, 10 NDB nodes (2 replica)
and only 2 api but i plan to add some mode.
all theses computers are 3GHz P4 with 1Go RAM each

the network is 100M ethernet (I plan to upgrade to gigabit)

I'm trying to fill my tables with a huge list of INSERT commands.

mysql databasename <myfile.sql

it is VERY slow!

then, i tried to use a large number of process.

mysql databasename <myfile_part01.sql &
mysql databasename <myfile_part02.sql &
mysql databasename <myfile_part03.sql &
[...]
mysql databasename <myfile_part30.sql &
mysql databasename <myfile_part32.sql &

It's faster but sometimes i've got

ERROR 1062 at line 34567: Duplicate entry '' for key 65

I double checked everything and I'm absolutely sure there are no identical lines in the input files. I'm also absolutely sure that theses lines don't have empty fields nor value '65'

If I drop everything and do it again, the line number always change but the error "Duplicate entry '' for key 65" is always the same. It seems to be a random error (concurrent access error ?)

I thought 32 process inserting data was too much and tried reducing the number of concurrent insert process.
in fact, the problem occurs with only two process.

what's the problem ???