We run all of our zones from one server, so I honestly have zero experience with this zone_servers issue.
As far as junctions (as they're called in NTFS) to network shares, it can be done with LSE (Link Shell Extensions).
http://schinagl.priv.at/nt/hardlinks...kshellext.html
Basically, you'll want to make c:\eqemu\quests pull from s:\eqemu\quests (where s:\ is a mapped network drive).
Dax