Extension name is not case insensitive in anymore
The extension "abaticker" for example contains something like:
In 6.2 this now fails with:
"TYPO3 Fatal Error: Extension key "abaTicker" is NOT loaded" (Exception 1365429656)
So the ExtensionManagementUtil API doesn't seem to be backwards compatible yet (i.e. extPath() etc), as it doesn't seem to expect different CaSe for the passed extension key.