Dealing with Canada Revenue Agency and Taxes on UN Income

I am consulting mostly with the UN system and keep hearing that this revenue is NOT taxable. However, trying to dig into the CRA web site, I cannot find any tax treaty between Canada and the UN system and my accountant keeps it in as part of my taxable income. Would anybody know of such thing? Or would you know the ruling on income say from UNDP, FAO, World Bank, etc.? Any help in this area would be greatly appreciated. You can respond to this mailing or directly at my contacts below.

Thanks a lot.