yes because of permgen leak, see previous page... I must use mvel because only if I use it I don't have permgen. drools version: 5.4.0.Final also on 5.5.0.Final -- View this message in context: http://drools.46999.n3.nabble.com/permgen-leak-tp4027038p4027115.html Sent from the Drools: User forum mailing list archive at Nabble.com.