Hi, I'm evaluating Guvnor 5.0CR1 and having problem when the MortgageApplicationTest example. It just fails with InvalidClassException, saying that serialVersionUID of MVELDialectRuntimeData are different. That doesn't make sense to me because I'm using absolute paths to point the server side jars. The version I'm using is "Drools 5.0.0.CR1 Guvnor Standalone". $ java -Dfile.encoding=UTF-8 -classpath /Users/yusukey/jbproject/ droolstest/target/classes:/Users/yusukey/jboss-eap-4.3cp03/server/ default/deploy/drools-guvnor.war/WEB-INF/lib/drools- core-5.0.0.CR1.jar:/Users/yusukey/jboss-eap-4.3cp03/server/default/ deploy/drools-guvnor.war/WEB-INF/lib/drools-api-5.0.0.CR1.jar:/Users/ yusukey/jboss-eap-4.3cp03/server/default/deploy/drools-guvnor.war/WEB- INF/lib/mvel2-2.0.8pre1.jar com.notidiots.MortgageApplicationTest RuleAgent(MyConfig) INFO (Sat Mar 14 11:06:13 JST 2009): Configuring with newInstance=true, secondsToRefresh=30 RuleAgent(MyConfig) INFO (Sat Mar 14 11:06:13 JST 2009): Configuring package provider : URLScanner monitoring URLs: http://localhost:8080/drools-guvnor/org.drools.guvnor.Guvnor/package/mort... RuleAgent(MyConfig) EXCEPTION (Sat Mar 14 11:06:25 JST 2009): org.drools.rule.MVELDialectRuntimeData; local class incompatible: stream classdesc serialVersionUID = -3277457858074244250, local class serialVersionUID = 6582893639473442227. Stack trace should follow. java.io.InvalidClassException: org.drools.rule.MVELDialectRuntimeData; local class incompatible: stream classdesc serialVersionUID = -3277457858074244250, local class serialVersionUID = 6582893639473442227 One thing I may need to mention is that I needed to change one single line to compile MortgageApplicationTest.java as following: ---------------- - import org.drools.rule.FactType; + import org.drools.definition.type.FactType; ---------------- Any idea why? I'm attaching the full stack trace. Cheers, Yusuke