4.4 MCSnapshotResource mockPackageName ==> 'MonticelloMocks'

4.3 MCSnapshotResource mockPackageName ==> #'Tests-Monticello-Mocks'

which seems to be due to

'From Squeak4.4 of 18 December 2012 [latest update: #12305] on 19 
December 2012 at 9:43:45 pm'!

!MCMockPackageInfo methodsFor: 'as yet unclassified' stamp: 'cwp 
8/1/2003 20:31'!
packageName
     ^ 'MonticelloMocks'! !


No such method exists in 4.3, so some code pieces the package name together.

Cheers,
BOb