ORa-4030 on 9.2.0.5

We are getting ORA-4030 error. The PGA_AGGREGATE_TARGET is 500M with 1.1GB SGA. What are the possible causes of the problem?

Following are the someof the errors in the alert.log? Is there any bug related to the heap size on HP11.11 and Oracle 9.2.0.5?

ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 263168 bytes
(callheap,kllcqgf:kllsltba)

ORA-04030: out of process memory when trying to allocate 263168 bytes
(callheap,kllcqgf:kllsltba)

ORA-04030: out of process memory when trying to allocate 263168 bytes
(callheap,kllcqgf:kllsltba)

ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 32792 bytes
(hash-join subh,QERHJ Bit vector)

ORA-04030: out of process memory when trying to allocate 263168 bytes
(callheap,kllcqgf:kllsltba)

ORA-04030: out of process memory when trying to allocate 33816 bytes (pga heap,control file i/o buffer)
ORA-04030: out of process memory when trying to allocate 8216 bytes
(koh-kghu

call ,koh koplds)

Thanks,
Raja

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