[ https://issues.jboss.org/browse/DROOLS-665?page=com.atlassian.jira.plugin... ] Davide Sottara commented on DROOLS-665: --------------------------------------- We know that the extension mechanism is not perfect, to this date you can only extend rules within the same package. This mechanism, however, should work even across mutiple drls - see the unit tests in https://github.com/droolsjbpm/drools/blob/dd59435b623cc5dfdbb3ba9b0ff18b1... This said, in your reproducer the base rule is called "Parend" while the child extends "parent". Since the mechanism uses string comparison, please double check the spelling in your original rulebase or submit a full reproducer. I will close this ticket for now, feel free to reopen it if you can isolate the problem. Best Davide -- This message was sent by Atlassian JIRA (v6.3.11#6341)