Problems with PostgreSQL 6.5.2 on Irix 6.2

Problems with PostgreSQL 6.5.2 on Irix 6.2

I just finished compiling postgresql for the first time on mu Indy.  I
installed the system and then began to follow the instructions on
testing the backend.  I ran the initdb OK.  I then started the
postmaster.  When I ran the createdb this is what I got:

FATAL: s_lock(004000c0) at spin.c:125, stuck spinlock. Aborting.

FATAL: s_lock(004000c0) at spin.c:125, stuck spinlock. Aborting.
IpcMemoryCreate: shmget failed (Invalid argument) key=5432101,
size=1073152, permission=600
FATAL 1:  ShmemCreate: cannot create region
NOTICE:  Message from PostgreSQL backend:
        The Postmaster has informed me that some other backend died
abnormally and possibly corrupted shared memory.
        I have rolled back the current transaction and am going to
terminate your database system connection and exit.
        Please reconnect to the database system and repeat your query.

Can anyone tell me what this means?

-gerald