In response to the recently released Corda 4.0 Corda 3.4 brings a number of fixes that address several interoperability issues we've discovered between nodes. These should make the deployment of mixed version networks far smoother and the upgrade path from 3 to 4 easier.

The majority of these fixes surround the serialisation and class synthesis frameworks where receiving states and messages from newer (Version 4) nodes highlighted a few edge cases, bugs, and performance enhancements we could make.

Issues Fixed

Don't fail deserialisation with carpentry errors if the carpented types would be discarded through evolution [CORDA-2704] RPC Vault query incompatibility between Corda 3.3 and Corda 4 [CORDA-2687] V3 node unable to record finalised transaction containing a V3 FungibleAsset state created by a V4 node [CORDA-2422] V3 node is unable to evolve serialised type that has introduced a property that is of an unknown type [CORDA-2314] ClassCastException during initiate Contract Upgrade [CORDA-2109]