hi igor up to 11125 it works well and after when I was trying to do the last two cs using MC in 11125 I get new ^ self trailerClass basicNew initialize trailerClass ^ TrailerClass ifNil: [ OldMethodTrailer ] in 11126 when I try to load these packages. I get CompiledMethodTrailer new does understand trailerClass Stef (now I have to run downtown with my boys and I will come back in 2hours or so). CompiledMethodTrailer class(Object)>>doesNotUnderstand: #trailerClass CompiledMethodTrailer class>>new CompiledMethod>>trailer CompiledMethod>>getSourceFor:in: Metaclass(Behavior)>>sourceCodeAt:ifAbsent: Metaclass(Behavior)>>ultimateSourceCodeAt:ifAbsent: Browser(CodeHolder)>>sourceStringPrettifiedAndDiffed Browser>>selectedMessage Browser>>contents PluggableTextMorph>>getText PluggableTextMorph>>update: [] in Browser(Object)>>changed: DependentsArray>>do: Browser(Object)>>changed: Browser(Object)>>contentsChanged Browser(CodeHolder)>>contentsChanged Browser>>messageListIndex: PluggableListMorph>>changeModelSelection: PluggableListMorph>>mouseUp: PluggableListMorph(Morph)>>handleMouseUp: MouseButtonEvent>>sentTo: PluggableListMorph(Morph)>>handleEvent: MorphicEventDispatcher>>dispatchDefault:with: MorphicEventDispatcher>>dispatchEvent:with: PluggableListMorph(Morph)>>processEvent:using: PluggableListMorph(Morph)>>processEvent: PluggableListMorph>>handleFocusEvent: [] in HandMorph>>sendFocusEvent:to:clear: [] in PasteUpMorph>>becomeActiveDuring: BlockClosure>>on:do: PasteUpMorph>>becomeActiveDuring: HandMorph>>sendFocusEvent:to:clear: HandMorph>>sendEvent:focus:clear: HandMorph>>sendMouseEvent: HandMorph>>handleEvent: HandMorph>>processEvents [] in WorldState>>doOneCycleNowFor: Array(SequenceableCollection)>>do: WorldState>>handsDo: