Jaybird (2.2.x) supports the following specifications
JDBC 4.1
Driver implements all JDBC 4.1 methods added to existing interfaces. The driver explicitly supports closeOnCompletion, most other JDBC 4.1 specific methods throw SQLFeatureNotSupportedException.
JDBC 4.0
Driver implements all JDBC 4.0 interfaces and supports exception chaining.
JDBC 3.0
Driver implements all JDBC 3.0 interfaces (but will throw FBDriverNotCapableException for some methods)
Outdated information regarding JDBC 3.0 support below
Jaybird 2.0 passed complete JDBC CTS 1.3.1 compatibility test suite, though some JDBC 3.0 features are not implemented. The exact list of unsupported features can be found in release notes.
JCA 1.0
Jaybird provides implementation of javax.resource.spi.ManagedConnectionFactory and related interfaces. CCI interfaces are not supported.
Although Jaybird depends on the JCA 1.5 classes, JCA 1.5 (and higher) compatibility is currently not guaranteed.
JTA 1.0.1
Driver provides implementation of javax.transaction.xa.XAResource interface via JCA framework and javax.sql.XADataSource implementation.
JMX 1.2
Jaybird provides MBean that allows creating and dropping databases via JMX agent.