Hi All, I've updated http://ftp.squeak.org/Cog with new source, OpenSourceCog-oscog.16.tar.gz/VMMaker-oscog.16.mcz that fixes the three issues people have found: Nicholas' crash on loading SUnit.dtl.?? which was a very nasty bug in the GC'ing of some trace logs the VM maintains. It was down to a difference between Smalltalk's \\ and C's %, specifically that the latter can answer something of different sign to the modulus. The failure of GeneratorTest, superficially due to cannotReturn: crashes, but fundamentally to do with inter-page returns to frames within the page not preserving the frames above, which can be in use due to co-routining (swapSender: usage). I hope this will fix Seaside on Cog. Please let me know. Crashes due to temps occurring in very simple blocks (that Cog compiles frameless) e.g. [ | b | 5 ] value. HTH Eliot