Itamar, are there any other "special" custom properties we are providing that don't require a hook?

./backend/manager/dbscripts/upgrade/pre_upgrade/0000_config.sql:select fn_db_add_config_value('PredefinedVMProperties','

sap_agent=^(true|false)$;
sndbuf=^[0-9]+$;
vhost=^(([a-zA-Z0-9_]*):(true|false))(,(([a-zA-Z0-9_]*):(true|false)))*$;viodiskcache=^(none|writeback|writethrough)$

','3.1');

but other than sap_agent, and maybe sndbuf, your normal customer isn't supposed to need the other two in day to day.

Red_Hat_Enterprise_Virtualization-Administration_Guide-3.1-web-en-US-2-96.el6