Shimano cantilever BR-M732 asymmetry

Last weekend, I installed Shimano cantilever brake BR-M732, which is
sometimes called 'XT2', or 'XT-II" as I understand it.

I found that the arm with secondary spring tension adjustment has more drag
at the pivot than the other arm. This causes the two arms to respond
asymmetrically when the brake cable is pulled or released.

The drag appears to be integral to that cantilever arm; different greases
and lubes on the brake bosses did not correct for the differential.
Loosening or tightening the pivot bolt had no affect. Unequal left/right
spring tension and/or straddle cable length do not directly address this
problem.

With some Googling, I found a post referring to this issue:
http://tinyurl.com/6273n, or
http://groups.google.co.uk/groups?hl...%40crcnis1.unl.
edu

Has anybody else here experienced this? Did Shimano make a running change
to the 732 to correct the issue? Does the 730 have the same problem?

Thanks,
Nicholas