libz.so.1 conflict/compatibility issue

[Ken Teague <kteague@pobox.com>]

Debian Lenny

I have a commercial application called acuSim under /usr/local/bin/acusim.  It also installed libz.so.1.2.3 under /usr/local/bin/acusim/LINUX64/V1.7e/base/lib.  This library is causing major problems on my box.  For example, if I try to start Iceweasel, it segfaults.  gnome-session spews out tons "symbol lookup error: /usr/lib/libxml2.so.2: undefined symbol: gzopen64" errors, as well as epiphiny-browser.  After running "strace -eopen /usr/X11R6/bin/epiphany-browser 2>&1 | grep libz", I got this:

open("tls/x86_64/libz.so.1", O_RDONLY)  = -1 ENOENT (No such file or directory)
open("tls/libz.so.1", O_RDONLY)         = -1 ENOENT (No such file or directory)
open("libz.so.1", O_RDONLY)             = -1 ENOENT (No such file or directory)
open('/usr/local/bin/acusim/LINUX64/V1.7e/bin/libz.so.1", O_RDONLY) = -1 ENOENT (No such file or directory)

So, after seeing that last line, I did the following:
  cd /usr/local/bin/acusim/LINUX64/V1.7e/bin
  mv libz.so.1 libz.so.1.orig

After this, all of the packages that appeared to be broken started to work again.  I could launch Iceweasel, gnome-session, epiphany-brower, the whole 9 yards, without a problem.

libz.so.1, of course, is a symlink to the actual library.  For my Debian Lenny box, it points to libz.so.1.2.3.3 and for acusim, it points to libz.so.1.2.3.

My question is how can I get the two libz.so.1 files to exist and play nicely together?  Thanks in advance.

- Ken