Yeah, it's definitely to use the JTA with Java 9. Currently we have a jta-module to export the jta packages narayana/ArjunaJTA/jta-module at jdk9-experimental · jbosstm/narayana · GitHub
you could use the option with "--upgrade-module-path /path/to/directory/"
Also we are looking into the issue with automatic module add Module Name to manifest for automatic module usage in Java 9 by paulbakker · Pull Request #5 · jboss/jboss-transacti…
and the discuss about the split package Split package with java.sql module in Java 9 · Issue #4 · jboss/jboss-transaction-api_spec · GitHub