Nicolas Cellier uploaded a new version of System to project The Trunk:
http://source.squeak.org/trunk/System-nice.505.mcz

==================== Summary ====================

Name: System-nice.505
Author: nice
Time: 30 December 2012, 8:18:04.984 pm
UUID: ecd50a53-d129-4d62-b65b-d456f7444019
Ancestors: System-bf.504

Correct MessageTally spyOn: [] MNU on new COG VM

=============== Diff against System-bf.504 ===============

Item was changed:
  ----- Method: MessageTally>>computeGCStats (in category 'private') -----
  computeGCStats
  	"Compute the deltas in the GC stats.  Serves for reporting, hibernating and unhibernating."
  	SmalltalkImage current getVMParameters keysAndValuesDo:
  		[ :idx :gcVal |
+ 		gcVal isNumber ifTrue: [gcStats at: idx put: (gcVal - (gcStats at: idx))]]!
- 		gcVal ifNotNil: [gcStats at: idx put: (gcVal - (gcStats at: idx))]]!