Rule Definition
An enterprise bean must not use read/write static fields. Using read-only static fields is allowed. Therefore, it is recommended that all static fields in the enterprise bean class be declared as final. This rule is required to ensure consistent runtime semantics because while some EJB containers may use a single JVM to execute all enterprise bean's instances, others may distribute the instances across multiple JVMs.

Remediation
Declare these static fields as final or review your design.

Violation Code Sample

@Stateful
public class MyBean implements MyRemoteBean {
   private static String myName = "MyBean"; // VIOLATION
    ...
    public int aMethod() {
        ...
    }
   ...
}

Fixed Code Sample

@Stateful
public class MyBean implements MyRemoteBean {
   private static final String myName = "MyBean"; // FIXED
    ...
    public int aMethod() {
        ...
    }
   ...
}

JSR-220 Enterprise Java Beans 3.0 Final Release (ejbcore) page 545