Enquiry about validity of multiple entry visa

[ha-sa]

Hi,

I an an international student in Canada with a valid study permit until November 2011. I have a multiple entry visa with expiry date Jan 27, 2011. I was wondering if I can re-enter Canada on December 30, 2010 (less than a month before the expiration of the visa). Do I need to re-enter Canada one month before the expiration of my multiple entry visa?

Thanks