A list of jndiServices is kept up to date and the jpa-container bundles waits for a matching service to be available.
However it only supports the following syntax:

<jta-data-source>osgi:service/jdbc/DataSource</jta-data-source>

and not the equivalent

<jta-data-source>osgi:service/javax.sql.DataSource/(osgi.jndi.service.name=jdbc/DataSource)</jta-data-source>

This is a regression.