Is it ora-04031 ?
ok

i feel you need to reconfigure your Unix kernel interprocess communication parameters to accomodate the SGA structure of the Oracle server.

obtain a list of the system's current shared memory and semaphore segments and try and reset the SHMMAX & SHMSEG parameters according to your requirement (keeping in mind the number of separate instances you are going to have on your server)

The total allowable shared memory is determined by the formula SHMMAX * SHMSEG.

Do make sure to rebuild the kernel if you have changed the semaphore parameters.

This might be a possible solution to the above problem. i had once faced such a problem and i had solved it in the same way .

I might be wrong in my guess though.