I've uploaded new VMs to
VM.r2348/ (SimpleStackBasedCogit) and
VM.r2349/ (StackToRegisterMappingCogit). The former are simply to be up-to-date with svn & Monticello. The latter also fix a bad bug with the StackToRegisterMappingCogit where e.g. 16r10 bitOr: 16r20 would evaluate to 1. I've smoke-tested the 2349 VMs on the Squeak4.2 beta test suite and things look good.