Hi folks, I'm doing some very basic evaluation of Drools and can't get past the first hurdle - the hello world example. I get this: ...... Caused by: java.lang.RuntimeException: The Eclipse JDT Core jar is not in the classpath at org.drools.rule.builder.dialect.java.JavaDialectConfiguration.setCompiler(JavaDialectConfiguration.java:94) at org.drools.rule.builder.dialect.java.JavaDialectConfiguration.init(JavaDialectConfiguration.java:55) at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:270) I'm not using Eclipse, my IDE is netbeans 6.8. I get the same error running the compiled jar from outside netbeans as well so I don't think it's related to the IDE. I modified the example by adding a knowledge builder config and then this: kconfig.setProperty("drools.dialect.java.compiler", "JANINO"); This had no effect. I rewrote the example to use a package builder and set the compiler property on it to JANINO. Again, it didn't work. I also tried passing a -Dproperty with the same thing. Again, no effect. I have the janino jar from the download on the classpath along with the other jars it says are necessary. It works if I download and add the eclipse jar to the classpath but I don't want to do this as I don't want my runtime app to depend on pieces of eclipse. I'm out of time and ideas now so asking for help here. These are the drools related jars I have in the project: antlr-runtime-3.1.1.jar drools-api-5.0.1.jar drools-compiler-5.0.1.jar drools-core-5.0.1.jar joda-time-1.6.jar mvel2-2.0.10.jar janino-2.5.15.jar xstream-1.3.1.jar Thanks, Martin