From: Reid Thompson <reid.thompson@...>
Date: 2010-03-03T01:24:00+09:00
Subject: Re: Installing Pg gem for PostGreSQL 8.4

On Tue, 2010-03-02 at 23:09 +0900, Saeed Bhuta wrote:
> Reid Thompson wrote:
> > On Tue, 2010-03-02 at 17:24 +0900, Saeed Bhuta wrote:
> >> >> 
> >> /usr/lib
> >> 
> >> pg_config --bindir
> >> /usr/lib/postgresql/8.4/bin
> > 
> > what does
> > $ ls -lrt /usr/lib/*libpq*
> > 
> > return
> 
> 
> ls -lrt /usr/lib/*libpq*
> -rw-r--r-- 1 root root 217474 2009-09-09 17:51 /usr/lib/libpq.a
> -rw-r--r-- 1 root root 151036 2009-09-09 17:51 /usr/lib/libpq.so.5.2
> lrwxrwxrwx 1 root root     12 2009-11-30 12:12 /usr/lib/libpq.so.5 -> 
> libpq.so.5.2
> lrwxrwxrwx 1 root root     12 2010-03-02 10:12 /usr/lib/libpq.so -> 
> libpq.so.5.2

ok - that all looks right so far.
per your original email 
> Check the mkmf.log file for more
> details.
what does mkmf.log contain?

on my box this file is located at

/usr/lib/ruby/gems/1.8/gems/pg-0.8.0/ext/mkmf.log

That may or may not be where your's is located.