There is code to support this, in particular the client_version_mask field in the doors and zonepoints tables.
Post 15 in this thread explains how the mask works:
http://www.eqemulator.org/forums/showthread.php?t=32701
The current PEQ database has entries for several revamped zones (including high pass hold) to send the various clients to the correct version, however this is currently broken in Underfoot. The SQL to fix it for Underfoot is here:
http://www.peqtgc.com/phpBB2/viewtopic.php?t=11639