I tried your solution on my newly installed 14.04, but I get this error : "Couldn't load XPCOM".
I spent two hours (really) trying everything I could find, to no result. Or more exactly, I made progress, step by step, until stumbling on that one.
The error is linked to XULrunner, so I wonder what you mean exactly when you write "including... adding an entry in my /etc/ld.so.conf.d area for /opt/zimbra/zdesktop/linux/prism/xulrunner". Can you tell me what you did? I mean, the exact command(s)... because my Linux skills are limited.
Thank you in advance!