When trying to update my trunk image I got problems with StrikeFont  
useUnderscore.
It seems to me that when a characterToGlyphMap is'nt there StrikeFont  
try to create one with createCharacterToGlyphMap but this does'nt seem  
to happen on my system so code break on 'nil' ....

This is what I understand..may be I'm totaly wrong.

=============
Error: Instances of UndefinedObject are not indexable
6 August 2009 11:37:20.388 am

VM: Mac OS - a SmalltalkImage
Image: Squeak3.10.2 [latest update: #7179]

SecurityManager state:
Restricted: false
FileAccess: true
SocketAccess: true
Working Dir /Users/ray1/Documents/PROGRAMMATION/ATELIER TRUNK/ 
Squeak3102Trunk
Trusted Dir /foobar/tooBar/forSqueak/bogus
Untrusted Dir /Users/ray1/Library/Preferences/Squeak/Internet/My Squeak

UndefinedObject(Object)>>error:
	Receiver: nil
	Arguments and temporary variables:
		aString: 	'Instances of UndefinedObject are not indexable'
	Receiver's instance variables:
nil

UndefinedObject(Object)>>errorNotIndexable
	Receiver: nil
	Arguments and temporary variables:

	Receiver's instance variables:
nil

UndefinedObject(Object)>>at:put:
	Receiver: nil
	Arguments and temporary variables:
		index: 	96
		value: 	129
	Receiver's instance variables:
nil

StrikeFont>>useUnderscore
	Receiver: a StrikeFont(Japanese10 12)
	Arguments and temporary variables:

	Receiver's instance variables:
		characterToGlyphMap: 	nil
		xTable: 	a SparseLargeTable(-1 0 12 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1  
-1 -1 -1 -1...etc...
		glyphs: 	Form(225480x12x1)
		name: 	'Japanese10'
		type: 	0
		minAscii: 	92
		maxAscii: 	65533
		maxWidth: 	12
		strikeLength: 	nil
		ascent: 	10
		descent: 	2
		xOffset: 	nil
		raster: 	nil
		subscript: 	-3
		superscript: 	2
		emphasis: 	0
		derivativeFonts: 	#(nil nil nil nil nil nil nil nil nil nil nil nil  
nil nil nil ...etc...
		pointSize: 	9
		fallbackFont: 	nil
		charIndex: 	nil


--- The full stack ---
UndefinedObject(Object)>>error:
UndefinedObject(Object)>>errorNotIndexable
UndefinedObject(Object)>>at:put:
StrikeFont>>useUnderscore
  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
[] in StrikeFont class>>useUnderscore
Array(SequenceableCollection)>>do:
StrikeFont class>>useUnderscore
StrikeFont class>>installDejaVu
UndefinedObject>>DoIt
Compiler>>evaluate:in:to:notifying:ifFail:logged:
Compiler class>>evaluate:for:notifying:logged:
Compiler class>>evaluate:for:logged:
Compiler class>>evaluate:
MCPostscriptDefinition(MCScriptDefinition)>>evaluate
MCPostscriptDefinition>>postload
MCPostscriptDefinition(MCDefinition)>>postloadOver:
[] in [] in [] in MCPackageLoader>>basicLoad
[] in [] in  
OrderedCollection(SequenceableCollection)>>do:displayingProgress:
OrderedCollection(SequenceableCollection)>>withIndexDo:
[] in OrderedCollection(SequenceableCollection)>>do:displayingProgress:
[] in [] in ProgressInitiationException>>defaultMorphicAction
BlockClosure>>on:do:
[] in ProgressInitiationException>>defaultMorphicAction
BlockClosure>>ensure:
ProgressInitiationException>>defaultMorphicAction
ProgressInitiationException>>defaultAction
UndefinedObject>>handleSignal:
MethodContext(ContextPart)>>handleSignal:
MethodContext(ContextPart)>>handleSignal:
MethodContext(ContextPart)>>handleSignal:
MethodContext(ContextPart)>>handleSignal:
ProgressInitiationException(Exception)>>signal
ProgressInitiationException>>display:at:from:to:during:
ProgressInitiationException class>>display:at:from:to:during:
ByteString(String)>>displayProgressAt:from:to:during:
OrderedCollection(SequenceableCollection)>>do:displayingProgress:
[] in [] in MCPackageLoader>>basicLoad
BlockClosure>>on:do:
[] in MCPackageLoader>>basicLoad
BlockClosure>>ensure:
MCPackageLoader>>basicLoad
[] in MCPackageLoader>>loadWithNameLike:
[] in MCPackageLoader>>useChangeSetNamed:during:
BlockClosure>>ensure:
MCPackageLoader>>useChangeSetNamed:during:
MCPackageLoader>>useNewChangeSetNamedLike:during:
MCPackageLoader>>loadWithNameLike:
MCThreeWayMerger(MCMerger)>>loadWithNameLike:
MCVersionMerger>>mergeWithNameLike:
MCVersionMerger class>>mergeVersion:
MCDiffyVersion(MCVersion)>>merge
[] in [] in MCConfiguration>>upgrade
BlockClosure>>on:do:
[] in MCConfiguration>>upgrade
[] in MCConfiguration>>depsSatisfying:versionDo:displayingProgress:
[] in [] in  
OrderedCollection(SequenceableCollection)>>do:displayingProgress:
OrderedCollection(SequenceableCollection)>>withIndexDo:
[] in OrderedCollection(SequenceableCollection)>>do:displayingProgress:
[] in [] in ProgressInitiationException>>defaultMorphicAction
BlockClosure>>on:do:
[] in ProgressInitiationException>>defaultMorphicAction
-- and more not shown --