[rules-users] Using java.util.List in rules

Hi everyone, I'm trying to use a java.util.List like this: rule "Test" when e : Especialista(retratoUser.lstCarac.get(0).codCarac != 0) then System.out.println("test"); end The property lstCarac is a java.util.List<Caracteristica>. I'm getting this error : org.drools.rule.InvalidRulePackage: [18,44]: unknown:18:44 Unexpected token '0'[18,46]: unknown:18:46 Unexpected token '.' at org.drools.rule.Package.checkValidity(Package.java:419) Someone knows what i have to do to fix the problem?? -- Anderson Pazza Mello Tecnologia em Informática - UFPR