ERROR => shmat(11698206,0x(nil),SHM_RND) (12: Cannot allocate memory)

I am do a clean installation of NetWeaver 7.0 SR3. When it comes to the start instance phase, the WP could not be started. I have checked the dev_w0, there is an error says:

I  *** ERROR => shmat(11698206,0x(nil),SHM_RND) (12: Cannot allocate memory) [shmux.c      1593]

M  *** ERROR => ThShMCreate: ShmCreate SHM_ROLL_AREA_KEY failed [thxxhead.c   2757]

M  *** ERROR => ThIPCInit: ThShMCreate [thxxhead.c   2172]

M  ***LOG R19=> ThInit, ThIPCInit ( TSKH-IPC-000001) [thxxhead.c   1567]

I have 4 GB RAM and 20GB swap space, so I think this is not due to memory bottle neck.

Can anyone help me on this? Thanks in advance!

Regards,

Roy Liu