This works just fine on a Telus V710, with firmware version TELUS_1X_1.0F.2P, on Mac OS 10.4.10 and iSync 2.4.

I made the change using Property List Editor through my regular admin account, and there was no need to change any permissions afterwards. Both iSync and the enclosed MetaClasses.plist file have owner: system, and group: admin.

In a week or so, I may be trying to make it work on Leopard.

After I upgraded to Leopard, the plist file was reset. I tried editing it again, but had no luck connecting to the phone via bluetooth this time (Mac OS's Bluetooth could see it, but iSync never found it).

Reverted the plist, and everything seems to work fine via USB. Maybe I'll try again some time.

Now the phone appears with a big red stop sign over it in iSync, and doesn't show the phone prefs when I click on it. Trying to sync via USB returns "Warning: No device activated".

Removing and reinstalling the phone in iSync shows its presence, with the correct icon, but then returns "iSync is unable to locate the plug-in for this phone. To re-enable support, please reinstall this phone's plug-in." I had previously reset the plist to its original values and successfully re-synced the phone via USB. I wonder if the 10.5.1 upgrade broke USB syncing for this phone?

Now I can't sync it at all.