Problems after instaling PostgreSQL 7.0

I installed PostgreSQL 7.0 on Linux RedHat 6.2, then I ran the initdb
command without any problems or warnings. Then, when I try to run the psql
interactive monitor, I get the following error:

[postgres@x ~/bin]$ ./psql
./psql: error in loading shared libraries: libpq.so.2.1: cannot open shared
object file: No such file or directory

I've checked and the file libpq.so.2.1 does exist in the /lib directory.

Could you please help me with this?

Thanks in advance,

J. Mauricio Cuenca H.
mcuenca@Telesat.com.co