FYI from the new CEC 20th Edition.

4-026(b) Installation of neutral conductor

Where a service, feeder, or branch circuit requires a neutral conductor, it shall be installed
(a)in all seperately enclosed switches and circuit breakers;
(b)in all centres of distribution associated with the circuit;
(c)with all connections to the neutral being made in the enclosures and centres;and
(d)ins such a manner that any neutral conductor may be disconnected without disconnecting any other neutral conductor.

10-210 Conductor to be grounded

(1) For alternating-current wiring systems, the conductor to be grounded shall be as follows:
(a)single-phase, 2 wire-the identified conductor;
(b)single phase, 3-wire-the identified neutral conductor;
(c)multi-phase systems having one wire common to all phases - the identified neutral conductor;
(d)multi-phase systems having one phase grounded-the identified conductor;
(e)multi-phase systemsin which one phase is used as in Item (b)-the identified conductor.

(2)In any multi-phase system in which one phase is used as a single-phase 3-wire system, only one phase shall be grounded.

Hope that helps. Check your local code that is in effect. - This one is from the new 20th edition - 2006.