Chris Muller uploaded a new version of SMBase to project The Trunk:
http://source.squeak.org/trunk/SMBase-cmm.124.mcz

==================== Summary ====================

Name: SMBase-cmm.124
Author: cmm
Time: 9 February 2011, 10:35:19 pm
UUID: dc1c64c6-aed4-4911-92ae-0d125f63210a
Ancestors: SMBase-cmm.123

- Support for allowing individual items in the cache to be refreshed.

=============== Diff against SMBase-cmm.123 ===============

Item was changed:
  ----- Method: SMFileCache>>add: (in category 'services') -----
  add: aDownloadable 
  	"Conditionally download the downloadable object into the cache.
  	Return true on success, otherwise false."
+ 	aDownloadable downloadFileName isEmptyOrNil ifTrue: [ ^ false ].
- 
  	^(self includes: aDownloadable)
  		ifTrue: [true]
  		ifFalse: [self download: aDownloadable]!

Item was added:
+ ----- Method: SMFileCache>>remove: (in category 'services') -----
+ remove: aDownloadable 
+ 	"Remove aDownloadable from the cache, if it exists."
+ 	(self includes: aDownloadable) ifTrue:
+ 		[ aDownloadable cacheDirectory deleteFileNamed: aDownloadable downloadFileName ]!

Item was added:
+ ----- Method: SMPackageRelease>>refreshInCache (in category 'services') -----
+ refreshInCache
+ 	"Delete and re-download the file back into the cache.
+ 	Return true on success, otherwise false."
+ 	map cache remove: self.
+ 	^ self 
+ 		sha1sum: nil; 
+ 		ensureInCache!