Description of problem:
Customer complains that rules that used to work now result in Exceptions.
Mario has isolated the one-line fix necessary to fix this issue on Drools 5.3.
Please use the JIRA at  for test information.
Fixed by https://github.com/droolsjbpm/drools/commit/e02698b08b6ee88dd0ad713f541aeeef1b008aa2
Verified in ER4