CentOS - Dec 2008 - Prelink woes: libs not found that are (apparently) present.

Pursuing some rpm verify errors exposed while investigating my T'bird/FF
problem, a prelink -am gives this, and other, error.

prelink: /usr/lib/esc-1.0.0/xulrunner/xulrunner-bin: Could not find one
of the dependencies

Ran

# ldd /usr/lib/esc-1.0.0/xulrunner/xulrunner-bin|grep 'not found'
        libmozjs.so => not found
        libxpcom.so => not found
        libxul.so => not found

Ran

# locate libmozjs
/usr/lib/esc-1.0.0/xulrunner/libmozjs.so
/usr/lib/thunderbird-2.0.0.18/libmozjs.so
/usr/lib/xulrunner-1.9/libmozjs.so

# locate libxpcom.so
/usr/lib/esc-1.0.0/xulrunner/libxpcom.so
/usr/lib/thunderbird-2.0.0.18/libxpcom.so
/usr/lib/xulrunner-1.9/libxpcom.so

# locate libxul.so
/usr/lib/esc-1.0.0/xulrunner/libxul.so
/usr/lib/xulrunner-1.9/libxul.so

And then confirmed existence with

# ls -dl \
> /usr/lib/esc-1.0.0/xulrunner/libmozjs.so \
> /usr/lib/xulrunner-1.9/libmozjs.so \
> /usr/lib/thunderbird-2.0.0.18/libmozjs.so \
> /usr/lib/esc-1.0.0/xulrunner/libxpcom.so \
> /usr/lib/thunderbird-2.0.0.18/libxpcom.so \
> /usr/lib/xulrunner-1.9/libxpcom.so \
> /usr/lib/esc-1.0.0/xulrunner/libxul.so \
> /usr/lib/xulrunner-1.9/libxul.so
-rwxr-xr-x 1 root root   634720 May 24
2008 /usr/lib/esc-1.0.0/xulrunner/libmozjs.so
-rwxr-xr-x 1 root root     8888 May 24
2008 /usr/lib/esc-1.0.0/xulrunner/libxpcom.so
-rwxr-xr-x 1 root root 13751232 May 24
2008 /usr/lib/esc-1.0.0/xulrunner/libxul.so
-rwxr-xr-x 1 root root   747032 Nov 20
09:12 /usr/lib/thunderbird-2.0.0.18/libmozjs.so
-rwxr-xr-x 1 root root    13396 Nov 20
09:12 /usr/lib/thunderbird-2.0.0.18/libxpcom.so
-rwxr-xr-x 1 root root   771976 Nov 13
19:33 /usr/lib/xulrunner-1.9/libmozjs.so
-rwxr-xr-x 1 root root    17536 Nov 13
19:33 /usr/lib/xulrunner-1.9/libxpcom.so
-rwxr-xr-x 1 root root 20273336 Nov 13
19:33 /usr/lib/xulrunner-1.9/libxul.so

My /etc/ld.so.conf has

$ cat /etc/ld.so.conf
include ld.so.conf.d/*.conf

and that has

==== /etc/ld.so.conf.d/nvidia.conf ===/usr/lib/nvidia
==== /etc/ld.so.conf.d/qt4-i386.conf ===/usr/lib/qt4/lib
==== /etc/ld.so.conf.d/qt-i386.conf ===/usr/lib/qt-3.3/lib

Man for ldconfig says that /lib and /usr/lib are included by default. I
ran ldconfig with a -p and looked at the output. Sub-directories
mentioned in the above config files were seen and some of the
"standard" /lib and /usr/lib sub-directories. However, none of the
directories from the "ls -dl" above (/usr/lib/esc-1.0.0/xulrunner/,
/usr/lib/xulrunner-1.9/, /usr/lib/thunderbird-2.0.0.18) appeared in
there.

With the age of these things, I would have expected them to show.

Do I need to add files in /etc/ld.so.conf.d for these?

Were they supposed to be in there already?

The questions are prompted by investigation of google results, related
to my T'bird/FF problem, that yielded some statements that some needed
libraries were not found and adding entries to /etc/ld.so.conf would fix
it - but those were old posts, not RH or CentOS centric and generally I
considered them unreliable for now.

But once I saw ldd show not found, I reconsidered.

TIA
-- 
Bill