Spring comes with traditional support for the CCI (Common Client Interface) included in the JCA specification, along the lines of Spring's JDBC support. However, CCI was never particularly popular and has been superseded by specific data access and integration APIs for modern practical purposes. Let's therefore deprecate it as of Spring Framework 5.3, dropping our support completely in 6.0.
Even as of 6.0, CCI will still be usable with Spring: using its native API, or even with a custom fork of the old CCI support classes in Spring. We are just not going to ship official support in core Spring anymore.