RV: Error interno postgres 8.4

Hola,

Estamos teniendo problemas con nuestra base de datos, eventualmente se para cayendo y el error que sale es el siguiente:

[4312-cemdb-postgres-2012-11-15 15:56:58.132 COT]DETAIL: parameters: $1 =
'700000000000000002'
[4312-cemdb-postgres-2012-11-15 15:57:01.288 COT]PANIC: could not open
file "pg_xlog/00000001000000E200000015" (log file 226, segment 21):
Permission denied
[4312-cemdb-postgres-2012-11-15 15:57:01.288 COT]STATEMENT: COMMIT
This application has requested the Runtime to terminate it in an unusual
way.
Please contact the application's support team for more information.
[2392-[unknown]-[unknown]-2012-11-15 15:57:01.429 COT]LOG: connection
received: host=172.29.104.188 port=49493
[1992---2012-11-15 15:57:01.429 COT]LOG: server process (PID 4312) exited
with exit code 3
[1992---2012-11-15 15:57:01.429 COT]LOG: terminating any other active
server processes
[3648---2012-11-15 15:57:01.429 COT]WARNING: terminating connection
because of crash of another server process
[3648---2012-11-15 15:57:01.429 COT]DETAIL: The postmaster has commanded
this server process to roll back the current transaction and exit, because
another server process exited abnormally and possibly corrupted shared
memory.

Bueno nuestra base de datos esta sobre un Windows Server 2008 64-bits, PostgreSql 8.4 y aproximadamente manejamos 5 millones de registros.

Saludos,
Enrique Mestas