Warning message is issued for number of queries (see this example of a query https://github.com/droolsjbpm/jbpm/blob/master/jbpm-human-task/jbpm-human-task-jpa/src/main/resources/META-INF/Taskorm.xml#L407-L421 ) that looks like a valid JPQL, even more are written in the way they are suggested in the warning.
This issue happened to be a a problem as it's every time issued when query is used which makes a log file full of them in regular use case of jBPM.
There are in total 8 queries affected by this all in this file: https://github.com/droolsjbpm/jbpm/blob/master/jbpm-human-task/jbpm-human-task-jpa/src/main/resources/META-INF/Taskorm.xml
all of them use the suggested format in the JPQL.