psql: error while loading shared liabraries: psql: undefined symbol: get_progname

Hi All,
I have installed Fedora 2 (linux) on my system with
database postgresql. I have done initdb and createddb
and created all the tables. Till that it was
successful. It worked fine for one day. the next day
when I started the database and tried to do psql
 I got an error "psql: error while
loading shared liabraries: psql: undefined symbol:
get_progname". For few times I was able to use psql
and executed the statements like select, insert etc.
But next day when I done this I got this error. I
tried installing whole Fedora 2 again but the result
is same. 
Can any one tell me the reason why this is happening ?

Thanks 

Jagan

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