Hi, I ran your test with 5.1.1 and there was no problem. FYI, this type of enquiry should normally be sent to the drools' users mailing list, not this dev' one. I assume you're using an older version; can you upgrade to 5.1.1? Cheers, Mike -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/Function-Definition-p... Sent from the Drools - Dev mailing list archive at Nabble.com.