jinxed - 1:02 pm on Nov 27, 2010 (gmt 0)
Adding the rel=nofollow to these links will not stop the 'leakage' of PR, so personally I wouldn't bother.
The only way to stop the leakage would be to remove the links completely.
I would think of it more from a user perspective. Are these functions helpful to your users? If yes then obviously keep them.