How long does CAN Passport need to be valid for TN

How long does a CAN passport need to be valid in order to get a TN? I always thought it had to be valid for at least 6 months from when you go to the border to get your TN, but I can not find information to support that. I would like to renew my TN this weekend at the border, but my passport will expire in late September 2010. I am only going to renew my TN for one year. Please advise!!!

(I am a Canadian working on Tn in the US)....

There is no requirement that your TN have validity concurrent with your passport. The 6 month requirement is for VISAS. TN is an entry status, and thus the only document requirement is the same one required for any Cdn entrant (curently valid passport by air, currently WHTI-valid document by land).

There have been recent problems at border by bored/frustrated CBP to somehow require that you have a fully charged passport -- but this is not required.