There is one log warning message which is not properly internationalized in Wildfly 'xts' submodule:

./src/xts/src/main/java/org/jboss/as/xts/GracefulShutdownRejectionRule.java:45: XTSLogger.logger.warnf("rejecting call because it is not part of any XTS transaction")
All logs of level WARN and higher should be internationalized.

The message above needs to be added to be added to the following file:

./XTS/sar/src/org/jboss/jbossts/xts/logging/xtsI18NLogger.java