thread safety on clients

Hi,

I compiled current HEAD and trying to use pgbench, i initialized a
test database this way:
bin/pgbench -i -F80 -s100 test

and then run with this options:
bin/pgbench -c 50 -j 5 -l -t 20 test

and get this crash:
"""
starting vacuum...end.
TRAP: FailedAssertion("!((data - start) == data_size)", File:
"heaptuple.c", Line: 255)
Client 0 aborted in state 8. Probably the backend died while processing.
LOG: server process (PID 30713) was terminated by signal 6: Aborted
TRAP: FailedAssertion("!((data - start) == data_size)", File:
"heaptuple.c", Line: 255)
Client 8 aborted in state 8. Probably the backend died while processing.
LOG: terminating any other active server processes
WARNING: terminating connection because of crash of another server process
DETAIL: The postmaster has commanded this server process to roll back
the current transaction and exit, because another server process
exited abnormally and possibly corrupted shared memory.
"""

if i remove the -j option then it runs without a problem

--
Atentamente,
Jaime Casanova
Soporte y capacitación de PostgreSQL
Asesoría y desarrollo de sistemas
Guayaquil - Ecuador
Cel. +59387171157