FATAL: could not create shared memory segment: Invalid argument

2011-06-05 16:08:26 EEST FATAL:  could not create shared memory segment: Invalid argument
2011-06-05 16:08:26 EEST DETAIL:  Failed system call was shmget(key=5433001, size=278364160, 03600).
2011-06-05 16:08:26 EEST HINT:  This error usually means that PostgreSQL's request for a shared memory segment exceeded your kernel's SHMMAX parameter.  You can $
        If the request size is already small, it's possible that it is less than your kernel's SHMMIN parameter, in which case raising the request size or reconf$
        The PostgreSQL documentation contains more information about shared memory configuration.

just change the value on postgresql.conf -> shared_buffers to smaller value then kernel SHMMUX value.