[Bug-gnuzilla] Can't seem to run Icecat 17 alongside Firefox 20 on Fedora 18.

[Julian]

I noticed that ever since I updated Fedora 18, which brought the Firefox 
version from 17 to 20, I get this message any time I try to run IceCat 
(which is the 64-bit binary from http://ftp.gnu.org/gnu/gnuzilla/17.0/, 
http://ftp.gnu.org/gnu/gnuzilla/17.0/icecat-17.0.1-64bit.tar.gz):

XPCOMGlueLoad error for file /home/julian/icecat-17.0.1/libxpcom.so:
/home/julian/icecat-17.0.1/libssl3.so: version `NSS_3.14' not found 
(required by /usr/lib64/xulrunner/libxul.so)
Couldn't load XPCOM.

I asked on a few IRC channels and got a response on #gnu, where we 
deduced that the problem is that, for some reason, IceCat is in some 
cases loading the system shared object files when it should be loading 
the shared object files contained in the IceCat directory.

We tried setting the environment variable LD_LIBRARY_PATH to the IceCat 
directory, but that made no difference. The same error occurred. I can 
also confirm that libxul.so is indeed in my IceCat directory.

The user on #gnu who helped me mentioned that, in the past, they had 
successfully installed a Firefox (64-bit) binary alongside a different 
version of Firefox by setting LD_LIBRARY_PATH to the custom Firefox's 
directory. I was unable to confirm from the user whether the version of 
Firefox he had installed was older or newer.

What do you think? Is there something wrong with the attempted solution 
(maybe a different environment variable is used now)? Is this an oddity 
in IceCat? Or is this maybe an upstream bug that the user on IRC didn't 
encounter by chance?