I'm seeing this in various classes in the System Browser. I'm selecting
a class, then "-- all --"  or a method category, then a method, then
going back to the class and doing a "spawn hierarchy". I'm giving the
method protocol because the problem seems to be grouped this way (but
the same methods will give the same error even when "-- all --" is
selected) -- the index matches the selector's position in the list for
its category.

Scanner 
    expression types
        #scanLitWord
	#scanStringStruct
	#scanToken
	#step

MethodNode
    code generator
	#generate
	#generateIfQuick
	#selector
	#sourceMap

MessageNode
    macro transformations
	all except #toDoFromWhileWithInit:

This is in Squeak2.5test - last update 1323.

-- Dwight