libreadline.so.3

Hi there,

I have installed postgresql before (7.1.*, BTW, how can I
check what version I am using after the installation - where can I get the
version information?). Recently, the linux server is rebooted and
upgraded. Since I am not the su, I have to rerun pgsql server. But when I
tried as usual to restart the database server, I got error message this time
as 'cannot open libreadline.so.3: no file exist'. there're several library files
available as:

libreadline.a libreadline.so.4 librep.a librep.so.9 libresolv.a
libreadline.so libreadline.so.4.2

what should I do to make pgsql recognize the library files in my system, while
not just the one it expectes?

Thanks a lot,

Yan