As detailed in
SPRNET-1438, the (temporary) resolution to that issue was to effectively DISABLE the 'TransactionSynchronization' extensibilty points in the AbstractPlatformTransactionManager until such time as this specific Tx nesting use-case is properly handled by the 'Suspend' and 'Resume' elements of the Tx Sync process. The estimation is that this extension point in Spring is "deep in the guts of the fwk" and so very unlikley to be something that consumers of the fwk have taken a dependency upon. Those that have taken this dependency can still explicitly choose the prior default of TransactionSynchronization.Always if they so choose/need.
As this issue exists in the Java codebase as well, a careful reconsideration of the handling of suspended/resumed transactions will need to be undertaken to properly address the specific use-case demonstrated in