Ok you are now going to a different context altogether with the possibility of a lay off. No one is ever 100% guaranteed to keep his job when he walks in the next day (economic crisis or no economic crisis - does not make a difference). Being positive in life and at work is the best thing you can do to keep your job. And that applies to all of us.
You did not read my previous post carefully and you are freaking out for nothing. May be you never saw a T4 or a notice of assessment and are confusing them with your paycheque. So, I'll break it down for you in further details - In January 2009 your company will send you a T4 that only shows how much you made in 2008 - no mention of months or hours worked whatsoever. After you have filed your taxes, CRA will send you a notice of assessment based on your T4 - showing how much you made, how much taxes you paid or credits you got. Once again - there is no mention of your hours or months you were employed.
In the light of the above, if you are still worried about the effect your unpaid vacation may have tne you have 2 options I guess:
1) do not take the unpaid vacation
or
2) take the upaid vacation and then only apply when you have worked actually worked for 1 or 2 years - whichever applies