The Tiger Build 56 replaced the way how Swing components deal with clipboard and this resulted in compatibility problems in NetBeans. Most of them get resolved, thanks to help of Igor Kushnirskiy and NetBeans does not have a problem anymore.

However I'd like to point out an incompatibility in a way how tiger b56 deals with SecurityManager:

In older versions <= b55 it was possible to prevent swing from accessing system clipboard just by overriding SecurityManager.checkSystemClipboardAccess and the swing would silently fallback to use its own clipboard.

This does not work anymore, if used swing will complain by printing an error message to the console (which scares NetBeans users).