Hi, I have a rule rule "rule 1" when Cheese(color.trim == "yellow") then System.out.println("hmm.. its yellow"); will raise : org.drools.spi.ConsequenceException: org.drools.RuntimeDroolsException: Exception executing predicate org.drools.base.mvel.MVELPredicateExpression@19adc2c I suspect it's because of the "trim" function. Does it allowed ? Is there any alternative ? I need this function because "Cheese" is loaded from database, and all the fields comes with space trailing. Thanks -- View this message in context: http://www.nabble.com/Using-trim-in-LHS-cause-%22Exception-executing-pred... Sent from the drools - user mailing list archive at Nabble.com.