Hy

I get the following error:

...

   Caused by: org.drools.RuntimeDroolsException: Unable to load dialect 'org.drools.rule.builder.dialect.mvel.MVELDialectConfiguration:mvel:org.drools.rule.builder.dialect.mvel.MVELDialectConfiguration'
        at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:313)
        ...
        ... 42 more
    Caused by: java.lang.ClassCastException: org.drools.rule.builder.dialect.mvel.MVELDialectConfiguration cannot be cast to org.drools.compiler.DialectConfiguration
        at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:308)
        ... 51 more

I'm using drools in a maven project, pom.xml:

...

    <dependency>
        <groupId>org.drools</groupId>
        <artifactId>drools-compiler</artifactId>
        <version>5.5.0.Final</version>
    </dependency>
    <dependency>
        <groupId>org.drools</groupId>
        <artifactId>drools-core</artifactId>
        <version>5.5.0.Final</version>
    </dependency>

...

What could cause this error?

Thanks for your help.

Kind regards,

Peter