Hi,
Renaming of classes in ADOxx is not possible. But you can copy one class within your application library. After you selected the the 'superclass' from which the copied class should be inherited, you can give this class a name. Afterwards, it is up to you, if you want to delete the original class. 
NOTE: Please check library on errors as it can occur some mis-matches because of previous definitions e.g.: MODI, InterRefs, ...