Problem with standby

Dear pgsql-testers

i have installed postgresql 9.0 beta1 and testing its streaming replication feature
when i set up the replication env (i.e. primary and standby servers) everything was fine and the replication goes successful but last three-four days the standby server does not doing replication i have appended the log messages that i received in standby server

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LOG:  could not recognize system time zone
DETAIL:  The PostgreSQL time zone will be set to "Etc/GMT-5".
HINT:  You can specify the correct timezone in postgresql.conf.
LOG:  database system was shut down in recovery at 2010-09-08 17:26:47 ETC/GMT
LOG:  entering standby mode
LOG:  redo starts at 23/8300F5D4
LOG:  consistent recovery state reached at 23/9A4DFFAC
LOG:  invalid magic number 0000 in log file 35, segment 154, offset 5111808
LOG:  database system is ready to accept read only connections
LOG:  streaming replication successfully connected to primary
FATAL:  could not receive data from WAL stream: FATAL:  requested WAL segment 00000001000000230000009A has already been removed
   
LOG:  streaming replication successfully connected to primary
FATAL:  could not receive data from WAL stream: FATAL:  requested WAL segment 00000001000000230000009A has already been removed
   
LOG:  streaming replication successfully connected to primary
FATAL:  could not receive data from WAL stream: FATAL:  requested WAL segment 00000001000000230000009A has already been removed
   
LOG:  streaming replication successfully connected to primary
FATAL:  could not receive data from WAL stream: FATAL:  requested WAL segment 00000001000000230000009A has already been removed
   
LOG:  streaming replication successfully connected to primary
FATAL:  could not receive data from WAL stream: FATAL:  requested WAL segment 00000001000000230000009A has already been removed

.
.
.

endless repeats

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i have tried to increase the wal_keep_segments configuration but still error was not resolved
please guide me to correct this error

Thanks & Regards
Jai Soni
98931-88891

Elbiz Systems Pvt. Limited
201, Kanchan Sagar
A.B. Road Indore (M.P.) 452001 INDIA
(T): 0731 4067757
(F): 0731 4064021

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