Not pattern dereferencing a variable in a constraint is wrongly evaluated using the executable model

@Test
public void testNotWithDereferencingConstraint() {
    final String drl1 =
            "package org.drools.compiler\n" +
            "import " + Person.class.getCanonicalName() + ";\n" +
            "rule R when\n" +
            "  $p: Person( $name : name )\n" +
            "  not Person( name.length == $name.length )\n" +
            "then\n" +
            "end\n";

    KieSession ksession = getKieSession( drl1 );

    ksession.insert( new Person("test", 18) );
    assertEquals( 0, ksession.fireAllRules() );
}