--- a/Class.st	Mon Dec 21 16:43:33 2009 +0100
+++ b/Class.st	Mon Dec 21 19:59:20 2009 +0100
@@ -4622,7 +4622,7 @@
                 classFilename isNil ifTrue:[
                     guessedFileName := (Smalltalk fileNameForClass:self) , '.st'.
                 ].
-                source asFilename baseName = classFilename asFilename baseName ifTrue:[
+                source asFilename baseName = (classFilename ? guessedFileName) asFilename baseName ifTrue:[
                     sourceStream := sourceCodeManager getSourceStreamFor:self.
                 ]
             ].
@@ -5022,9 +5022,9 @@
 !Class class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Class.st,v 1.563 2009-12-11 16:50:15 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Class.st,v 1.564 2009-12-21 18:59:20 cg Exp $'
 !
 
 version_CVS
-    ^ '$Header: /cvs/stx/stx/libbasic/Class.st,v 1.563 2009-12-11 16:50:15 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Class.st,v 1.564 2009-12-21 18:59:20 cg Exp $'
 ! !