Input/Output Error Message

<p><font size="2">Hello,</font><p>        <font size="2">I had a question regarding an error message that I'm seeing
duringmy testing using Postgres version 7.2. I'm not sure if this is related to Postgres or a disk I/O related problem.
Anyhelp or tips to pinpointing the problem would also help. Thanks in advance.</font><p><font size="2">The error is as
follows:</font><br/>        <font size="2"> </font><br />        <font size="2">[ERROR:  cannot read    block 6093 of
<table_name>:Input/output error]</font><p><font size="2">Note: I purposely left out the table name in question.
Anyways,a few additional points:</font><p>        <font size="2">- there is a cron type script (i.e. runs at defined
timeintervals - one hour) which reads data from the postgres database</font><p>        <font size="2">- from the 'debug
logs',this message was "sporadically" generated. What I mean by that is there no pattern (in terms of time)         
whenthis error message occurs. In this particular case, the message only appeared on Sunday, June 16th and at varying 
               times during the day</font><p><font size="2">Any help would be appreciated. Thanks again.</font><p><font
size="2">BrianChu - S/W Verification Prime</font><br /><font size="2">JetNet Internetworking Services Inc.</font><br
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