If there is payment involved, then a T4 is necessary, and then the deduction applies against that T4. If there is no amount involved, then the authorities would have to certify the hours, so a form would need to be designed. We would need to work with CRA to define what exactly this form should look like and the type of information that should be on it. You want to keep it simple, to the extent that you're not encouraging abuse, of course. It's a difficult balance, and it's something we would need to work on closely with CRA, which is responsible for administering these things.
On June 9th, 2008. See this statement in context.