The latest OS X update, 10.4.6, adds official support for the RAZR V3c (as well as the V3x and others). Note that the Verizon version does not support calendar syncing. I’m not surprised as I’ve had mixed feedback about the calendar syncing. Supposedly there is also a bug in the Verizon version, maybe the result of Verizon altering everything to meet their “requirements”?
While inspecting the new iSync MetaClasses.plist, it’s interesting to see that there’s a Verizon-specific version of the V3c listed. I’d imagine that calendar syncing could be re-enabled by changing the appropriate key-value pair, but there’s probably a reason why it’s not supported by default.
It’s probably best to remove my plugin from /Library/PhonePlugins/ before or after the OS update. You’ll need to re-add your phone when the update is done.