The cause of the problem is that MethodReference >> #category was added to 
the System package, while was still included in Monticello as an extension 
method. I removed it from Monticello in Monticello-ul.335 (IIRC) and added 
a new mcm, in hope that it will fix this issue. You can continue the 
update if you recreate the method in the debugger.


Levente


On Sat, 12 Dec 2009, Casimiro de Almeida Barreto wrote:

> MCMethodDefinition class>>forMethodReference:
>
> forMethodReference: aMethodReference
>    | definition |
>    definition := self cachedDefinitions at: aMethodReference compiledMethod 
> ifAbsent: [].
>    (definition isNil
>        or: [definition selector ~= aMethodReference methodSymbol]
>        or: [definition className ~= aMethodReference classSymbol]
>        or: [definition classIsMeta ~= aMethodReference classIsMeta]
>        or: [definition category ~= aMethodReference category])
>            ifTrue: [definition := self
>                        className: aMethodReference classSymbol
>                        classIsMeta: aMethodReference classIsMeta
>                        selector: aMethodReference methodSymbol
>                        category: aMethodReference category
>                        timeStamp: aMethodReference timeStamp
>                        source: aMethodReference source.
>                    self cachedDefinitions at: aMethodReference 
> compiledMethod put: definition].
>    ^ definition
>
>
> MethodReference(Object)>>doesNotUnderstand: #category
>
>