Strange error, probably WAL-related

I've installed a fresh postgresql-7.1.2 on a Debian GNU/Linux, when
importing my first database from a dump I got this error:

ERROR:  ExecAppend: Fail to add null value in not null attribute
fc_state
FATAL 2:  ZeroFill(/data/postgres/pg_xlog/xlogtemp.1223) failed: No such
file or directory
Server process (pid 1223) exited with status 512 at Wed Jun  6 14:59:58
2001
Terminating any active server processes...
Server processes were terminated at Wed Jun  6 14:59:58 2001
Reinitializing shared memory and semaphores
DEBUG:  database system was interrupted at 2001-06-06 14:58:56 BST
DEBUG:  CheckPoint record at (0, 1522068)
DEBUG:  Redo record at (0, 1522068); Undo record at (0, 0); Shutdown
TRUE
DEBUG:  NextTransactionId: 615; NextOid: 18720
DEBUG:  database system was not properly shut down; automatic recovery
in progress...
DEBUG:  redo starts at (0, 1522132)
DEBUG:  open(logfile 0 seg 3) failed: No such file or directory
DEBUG:  redo done at (0, 50331512)
FATAL 2:  ZeroFill(/data/postgres/pg_xlog/xlogtemp.1224) failed: No such
file or directory
/usr/local/pgsql/bin/postmaster: Startup proc 1224 exited with status
512 - abort

and now the database cannot be started again. I have no idea where to
start looking...

-- 
Alessio F. Bragadini        alessio@albourne.com
APL Financial Services        http://village.albourne.com
Nicosia, Cyprus             phone: +357-2-755750

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