Chris Muller uploaded a new version of ReleaseBuilder to project The Trunk:
http://source.squeak.org/trunk/ReleaseBuilder-cmm.60.mcz

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

Name: ReleaseBuilder-cmm.60
Author: cmm
Time: 4 February 2011, 10:40:34.373 am
UUID: 362c2739-8e95-4cc1-8ade-a1beba388a87
Ancestors: ReleaseBuilder-cmm.59

fix

=============== Diff against ReleaseBuilder-cmm.59 ===============

Item was changed:
  ----- Method: ReleaseBuilderTrunk classSide>>switchTo42Repository (in category 'private') -----
  switchTo42Repository
  	| old41Repository |
  	MCMcmUpdater defaultUpdateURL: 'http://source.squeak.org/squeak42'.
  	old41Repository := MCRepositoryGroup default repositories
+ 				detect: [:each | each description includesSubString: 'squeak41'] ifNone: [nil].
- 				detect: [:each | each description includesSubString: 'squeak41'].
  	old41Repository
  		ifNotNil: [MCRepositoryGroup default removeRepository: old41Repository].
  	MCRepositoryGroup default addRepository: self releaseRepository!